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href="/en-US/docs/Glossary/Accessibility_tree">Accessibility tree</a></li><li><a href="/en-US/docs/Glossary/Accessible_description">Accessible description</a></li><li><a href="/en-US/docs/Glossary/Accessible_name">Accessible name</a></li><li><a href="/en-US/docs/Glossary/Adobe_Flash">Adobe Flash</a></li><li><a href="/en-US/docs/Glossary/Advance_measure">Advance measure</a></li><li><a href="/en-US/docs/Glossary/AJAX">Ajax</a></li><li><a href="/en-US/docs/Glossary/Algorithm">Algorithm</a></li><li><a href="/en-US/docs/Glossary/Alignment_Container">Alignment container</a></li><li><a href="/en-US/docs/Glossary/Alignment_Subject">Alignment subject</a></li><li><a href="/en-US/docs/Glossary/Alpha">Alpha (alpha channel)</a></li><li><a href="/en-US/docs/Glossary/ALPN">ALPN</a></li><li><a href="/en-US/docs/Glossary/API">API</a></li><li><a href="/en-US/docs/Glossary/Apple_Safari">Apple Safari</a></li><li><a href="/en-US/docs/Glossary/Application_context">Application context</a></li><li><a href="/en-US/docs/Glossary/Argument">Argument</a></li><li><a href="/en-US/docs/Glossary/ARIA">ARIA</a></li><li><a href="/en-US/docs/Glossary/ARPA">ARPA</a></li><li><a href="/en-US/docs/Glossary/Arpanet">ARPANET</a></li><li><a href="/en-US/docs/Glossary/Array">Array</a></li><li><a href="/en-US/docs/Glossary/ASCII">ASCII</a></li><li><a href="/en-US/docs/Glossary/Aspect_ratio">Aspect ratio</a></li><li><a href="/en-US/docs/Glossary/Asynchronous">Asynchronous</a></li><li><a href="/en-US/docs/Glossary/ATAG">ATAG</a></li><li><a href="/en-US/docs/Glossary/Attribute">Attribute</a></li><li><a href="/en-US/docs/Glossary/Authentication">Authentication</a></li><li><a href="/en-US/docs/Glossary/Authenticator">Authenticator</a></li><li><a href="/en-US/docs/Glossary/Bandwidth">Bandwidth</a></li><li><a href="/en-US/docs/Glossary/Base64">Base64</a></li><li><a href="/en-US/docs/Glossary/Baseline">Baseline</a></li><li><a href="/en-US/docs/Glossary/Beacon">Beacon</a></li><li><a href="/en-US/docs/Glossary/Bezier_curve">Bézier curve</a></li><li><a href="/en-US/docs/Glossary/bfcache">bfcache</a></li><li><a href="/en-US/docs/Glossary/BiDi">BiDi</a></li><li><a href="/en-US/docs/Glossary/BigInt">BigInt</a></li><li><a href="/en-US/docs/Glossary/Binding">Binding</a></li><li><a href="/en-US/docs/Glossary/Bitwise_flags">Bitwise flags</a></li><li><a href="/en-US/docs/Glossary/Blink">Blink</a></li><li><a href="/en-US/docs/Glossary/blink_element">blink element (<blink> tag)</a></li><li><a href="/en-US/docs/Glossary/Block">Block</a></li><li><a href="/en-US/docs/Glossary/Block_cipher_mode_of_operation">Block cipher mode of operation</a></li><li><a href="/en-US/docs/Glossary/Block-level_content">Block-level content</a></li><li><a href="/en-US/docs/Glossary/Boolean">Boolean</a></li><li><a href="/en-US/docs/Glossary/Bounding_box">Bounding Box</a></li><li><a href="/en-US/docs/Glossary/Breadcrumb">Breadcrumb</a></li><li><a href="/en-US/docs/Glossary/Brotli_compression">Brotli compression</a></li><li><a href="/en-US/docs/Glossary/Browser">Browser</a></li><li><a href="/en-US/docs/Glossary/Browsing_context">Browsing context</a></li><li><a href="/en-US/docs/Glossary/Buffer">Buffer</a></li><li><a href="/en-US/docs/Glossary/Cache">Cache</a></li><li><em><a href="/en-US/docs/Glossary/Cacheable" aria-current="page">Cacheable</a></em></li><li><a href="/en-US/docs/Glossary/CalDAV">CalDAV</a></li><li><a href="/en-US/docs/Glossary/Call_stack">Call stack</a></li><li><a href="/en-US/docs/Glossary/Callback_function">Callback function</a></li><li><a href="/en-US/docs/Glossary/Camel_case">Camel case</a></li><li><a href="/en-US/docs/Glossary/Canonical_order">Canonical order</a></li><li><a href="/en-US/docs/Glossary/Canvas">Canvas</a></li><li><a href="/en-US/docs/Glossary/Card_sorting">Card sorting</a></li><li><a href="/en-US/docs/Glossary/CardDAV">CardDAV</a></li><li><a href="/en-US/docs/Glossary/Caret">Caret</a></li><li><a href="/en-US/docs/Glossary/CDN">CDN</a></li><li><a href="/en-US/docs/Glossary/Certificate_authority">Certificate authority</a></li><li><a href="/en-US/docs/Glossary/Certified">Certified</a></li><li><a href="/en-US/docs/Glossary/Challenge">Challenge-response authentication</a></li><li><a href="/en-US/docs/Glossary/Character">Character</a></li><li><a href="/en-US/docs/Glossary/Character_encoding">Character encoding</a></li><li><a href="/en-US/docs/Glossary/Character_reference">Character reference</a></li><li><a href="/en-US/docs/Glossary/Character_set">Character set</a></li><li><a href="/en-US/docs/Glossary/Chrome">Chrome</a></li><li><a href="/en-US/docs/Glossary/CIA">CIA</a></li><li><a href="/en-US/docs/Glossary/Cipher">Cipher</a></li><li><a href="/en-US/docs/Glossary/Cipher_suite">Cipher suite</a></li><li><a href="/en-US/docs/Glossary/Ciphertext">Ciphertext</a></li><li><a href="/en-US/docs/Glossary/Class">Class</a></li><li><a href="/en-US/docs/Glossary/Clickjacking">Clickjacking</a></li><li><a href="/en-US/docs/Glossary/Closure">Closure</a></li><li><a href="/en-US/docs/Glossary/Cloud">Cloud</a></li><li><a href="/en-US/docs/Glossary/Cloud_computing">Cloud computing</a></li><li><a href="/en-US/docs/Glossary/CMS">CMS</a></li><li><a href="/en-US/docs/Glossary/Code_point">Code point</a></li><li><a href="/en-US/docs/Glossary/Code_splitting">Code splitting</a></li><li><a href="/en-US/docs/Glossary/Code_unit">Code unit</a></li><li><a href="/en-US/docs/Glossary/Codec">Codec</a></li><li><a href="/en-US/docs/Glossary/Color_space">Color space</a></li><li><a href="/en-US/docs/Glossary/Color_wheel">Color wheel</a></li><li><a href="/en-US/docs/Glossary/Compile">Compile</a></li><li><a href="/en-US/docs/Glossary/Compile_time">Compile time</a></li><li><a href="/en-US/docs/Glossary/Composite_operation">Composite operation</a></li><li><a href="/en-US/docs/Glossary/Computer_Programming">Computer Programming</a></li><li><a href="/en-US/docs/Glossary/Conditional">Conditional</a></li><li><a href="/en-US/docs/Glossary/Constant">Constant</a></li><li><a href="/en-US/docs/Glossary/Constructor">Constructor</a></li><li><a href="/en-US/docs/Glossary/Content_header">Content header</a></li><li><a href="/en-US/docs/Glossary/Continuous_Media">Continuous Media</a></li><li><a href="/en-US/docs/Glossary/Control_flow">Control flow</a></li><li><a href="/en-US/docs/Glossary/Cookie">Cookie</a></li><li><a href="/en-US/docs/Glossary/Copyleft">Copyleft</a></li><li><a href="/en-US/docs/Glossary/CORS">CORS</a></li><li><a href="/en-US/docs/Glossary/CORS-safelisted_request_header">CORS-safelisted request header</a></li><li><a href="/en-US/docs/Glossary/CORS-safelisted_response_header">CORS-safelisted response header</a></li><li><a href="/en-US/docs/Glossary/Crawler">Crawler</a></li><li><a href="/en-US/docs/Glossary/Credential">Credential</a></li><li><a href="/en-US/docs/Glossary/CRLF">CRLF</a></li><li><a href="/en-US/docs/Glossary/Cross_Axis">Cross Axis</a></li><li><a href="/en-US/docs/Glossary/Cross-site_scripting">Cross-site scripting (XSS)</a></li><li><a href="/en-US/docs/Glossary/CRUD">CRUD</a></li><li><a href="/en-US/docs/Glossary/Cryptanalysis">Cryptanalysis</a></li><li><a href="/en-US/docs/Glossary/Cryptographic_hash_function">Cryptographic hash function</a></li><li><a href="/en-US/docs/Glossary/Cryptography">Cryptography</a></li><li><a href="/en-US/docs/Glossary/CSP">CSP</a></li><li><a href="/en-US/docs/Glossary/CSRF">CSRF</a></li><li><a href="/en-US/docs/Glossary/CSS">CSS</a></li><li><a href="/en-US/docs/Glossary/CSSOM">CSS Object Model (CSSOM)</a></li><li><a href="/en-US/docs/Glossary/CSS_pixel">CSS pixel</a></li><li><a href="/en-US/docs/Glossary/CSS_preprocessor">CSS preprocessor</a></li><li><a href="/en-US/docs/Glossary/CLS">Cumulative Layout Shift (CLS)</a></li><li><a href="/en-US/docs/Glossary/Data_structure">Data structure</a></li><li><a href="/en-US/docs/Glossary/Database">Database</a></li><li><a href="/en-US/docs/Glossary/Debounce">Debounce</a></li><li><a href="/en-US/docs/Glossary/Decryption">Decryption</a></li><li><a href="/en-US/docs/Glossary/Deep_copy">Deep copy</a></li><li><a href="/en-US/docs/Glossary/Delta">Delta</a></li><li><a href="/en-US/docs/Glossary/Denial_of_Service">Denial of Service</a></li><li><a href="/en-US/docs/Glossary/Deno">Deno</a></li><li><a href="/en-US/docs/Glossary/CSS_Descriptor">Descriptor (CSS)</a></li><li><a href="/en-US/docs/Glossary/Deserialization">Deserialization</a></li><li><a href="/en-US/docs/Glossary/Developer_Tools">Developer Tools</a></li><li><a href="/en-US/docs/Glossary/Digest">Digest</a></li><li><a href="/en-US/docs/Glossary/Digital_certificate">Digital certificate</a></li><li><a href="/en-US/docs/Glossary/Digital_signature">Digital signature</a></li><li><a href="/en-US/docs/Glossary/Distributed_Denial_of_Service">Distributed Denial of Service</a></li><li><a href="/en-US/docs/Glossary/DMZ">DMZ</a></li><li><a href="/en-US/docs/Glossary/DNS">DNS</a></li><li><a href="/en-US/docs/Glossary/Doctype">Doctype</a></li><li><a href="/en-US/docs/Glossary/Document_directive">Document directive</a></li><li><a href="/en-US/docs/Glossary/Document_environment">Document environment</a></li><li><a href="/en-US/docs/Glossary/DOM">DOM (Document Object Model)</a></li><li><a href="/en-US/docs/Glossary/Domain">Domain</a></li><li><a href="/en-US/docs/Glossary/Domain_name">Domain name</a></li><li><a href="/en-US/docs/Glossary/Domain_sharding">Domain sharding</a></li><li><a href="/en-US/docs/Glossary/Dominator">Dominator</a></li><li><a href="/en-US/docs/Glossary/DOS_attack">DoS attack</a></li><li><a href="/en-US/docs/Glossary/DSL">DSL</a></li><li><a href="/en-US/docs/Glossary/DTLS">DTLS (Datagram Transport Layer Security)</a></li><li><a href="/en-US/docs/Glossary/DTMF">DTMF (Dual-Tone Multi-Frequency signaling)</a></li><li><a href="/en-US/docs/Glossary/Dynamic_typing">Dynamic typing</a></li><li><a href="/en-US/docs/Glossary/ECMA">ECMA</a></li><li><a href="/en-US/docs/Glossary/ECMAScript">ECMAScript</a></li><li><a href="/en-US/docs/Glossary/Effective_connection_type">Effective connection type</a></li><li><a href="/en-US/docs/Glossary/Element">Element</a></li><li><a href="/en-US/docs/Glossary/Encapsulation">Encapsulation</a></li><li><a href="/en-US/docs/Glossary/Encryption">Encryption</a></li><li><a href="/en-US/docs/Glossary/Endianness">Endianness</a></li><li><a href="/en-US/docs/Glossary/Engine">Engine</a></li><li><a href="/en-US/docs/Glossary/Entity">Entity</a></li><li><a href="/en-US/docs/Glossary/Entity_header">Entity header</a></li><li><a href="/en-US/docs/Glossary/Enumerated">Enumerated</a></li><li><a href="/en-US/docs/Glossary/eTLD">eTLD</a></li><li><a href="/en-US/docs/Glossary/Event">Event</a></li><li><a href="/en-US/docs/Glossary/Exception">Exception</a></li><li><a href="/en-US/docs/Glossary/EXIF">EXIF</a></li><li><a href="/en-US/docs/Glossary/Expando">Expando</a></li><li><a href="/en-US/docs/Glossary/Fallback_Alignment">Fallback alignment</a></li><li><a href="/en-US/docs/Glossary/Falsy">Falsy</a></li><li><a href="/en-US/docs/Glossary/Favicon">Favicon</a></li><li><a href="/en-US/docs/Glossary/Federated_identity">Federated identity</a></li><li><a href="/en-US/docs/Glossary/Fetch_directive">Fetch directive</a></li><li><a href="/en-US/docs/Glossary/Fetch_metadata_request_header">Fetch metadata request header</a></li><li><a href="/en-US/docs/Glossary/Fingerprinting">Fingerprinting</a></li><li><a href="/en-US/docs/Glossary/Firefox_OS">Firefox OS</a></li><li><a href="/en-US/docs/Glossary/Firewall">Firewall</a></li><li><a href="/en-US/docs/Glossary/First_contentful_paint">First Contentful Paint (FCP)</a></li><li><a href="/en-US/docs/Glossary/First_CPU_idle">First CPU idle</a></li><li><a href="/en-US/docs/Glossary/First_input_delay">First Input Delay (FID)</a><abbr class="icon icon-deprecated" 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Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Glossary/First_meaningful_paint">First Meaningful Paint (FMP)</a></li><li><a href="/en-US/docs/Glossary/First_paint">First Paint (FP)</a></li><li><a href="/en-US/docs/Glossary/First-class_Function">First-class Function</a></li><li><a href="/en-US/docs/Glossary/Flex">Flex</a></li><li><a href="/en-US/docs/Glossary/Flex_Container">Flex Container</a></li><li><a href="/en-US/docs/Glossary/Flex_Item">Flex Item</a></li><li><a href="/en-US/docs/Glossary/Flexbox">Flexbox</a></li><li><a href="/en-US/docs/Glossary/Flow_relative_values">Flow relative values</a></li><li><a href="/en-US/docs/Glossary/Forbidden_header_name">Forbidden header name</a></li><li><a href="/en-US/docs/Glossary/Forbidden_response_header_name">Forbidden response header name</a></li><li><a href="/en-US/docs/Glossary/Fork">Fork</a></li><li><a href="/en-US/docs/Glossary/Fragmentainer">Fragmentainer</a></li><li><a href="/en-US/docs/Glossary/FPS">Frame rate (FPS)</a></li><li><a href="/en-US/docs/Glossary/FTP">FTP</a></li><li><a href="/en-US/docs/Glossary/FTU">FTU</a></li><li><a href="/en-US/docs/Glossary/Function">Function</a></li><li><a href="/en-US/docs/Glossary/Fuzzing">Fuzz testing</a></li><li><a href="/en-US/docs/Glossary/Gamut">Gamut</a></li><li><a href="/en-US/docs/Glossary/Garbage_collection">Garbage collection</a></li><li><a href="/en-US/docs/Glossary/Gecko">Gecko</a></li><li><a href="/en-US/docs/Glossary/General_header">General header</a></li><li><a href="/en-US/docs/Glossary/GIF">GIF</a></li><li><a href="/en-US/docs/Glossary/Git">Git</a></li><li><a href="/en-US/docs/Glossary/Global_object">Global object</a></li><li><a href="/en-US/docs/Glossary/Global_scope">Global scope</a></li><li><a href="/en-US/docs/Glossary/Global_variable">Global variable</a></li><li><a href="/en-US/docs/Glossary/Glyph">Glyph</a></li><li><a href="/en-US/docs/Glossary/Google_Chrome">Google Chrome</a></li><li><a href="/en-US/docs/Glossary/GPL">GPL</a></li><li><a href="/en-US/docs/Glossary/GPU">GPU</a></li><li><a href="/en-US/docs/Glossary/Graceful_degradation">Graceful degradation</a></li><li><a href="/en-US/docs/Glossary/Grid">Grid</a></li><li><a href="/en-US/docs/Glossary/Grid_Areas">Grid Areas</a></li><li><a href="/en-US/docs/Glossary/Grid_Axis">Grid Axis</a></li><li><a href="/en-US/docs/Glossary/Grid_Cell">Grid Cell</a></li><li><a href="/en-US/docs/Glossary/Grid_Column">Grid Column</a></li><li><a href="/en-US/docs/Glossary/Grid_Container">Grid container</a></li><li><a href="/en-US/docs/Glossary/Grid_Lines">Grid Lines</a></li><li><a href="/en-US/docs/Glossary/Grid_Row">Grid Row</a></li><li><a href="/en-US/docs/Glossary/Grid_Tracks">Grid Tracks</a></li><li><a href="/en-US/docs/Glossary/Gutters">Gutters</a></li><li><a href="/en-US/docs/Glossary/gzip_compression">gzip compression</a></li><li><a href="/en-US/docs/Glossary/Hash">Hash</a></li><li><a href="/en-US/docs/Glossary/Head">Head</a></li><li><a href="/en-US/docs/Glossary/High-level_programming_language">High-level programming language</a></li><li><a href="/en-US/docs/Glossary/HMAC">HMAC</a></li><li><a href="/en-US/docs/Glossary/Hoisting">Hoisting</a></li><li><a href="/en-US/docs/Glossary/Host">Host</a></li><li><a href="/en-US/docs/Glossary/Hotlink">Hotlink</a></li><li><a href="/en-US/docs/Glossary/Houdini">Houdini</a></li><li><a href="/en-US/docs/Glossary/HPKP">HPKP</a></li><li><a href="/en-US/docs/Glossary/HSTS">HSTS</a></li><li><a href="/en-US/docs/Glossary/HTML">HTML</a></li><li><a href="/en-US/docs/Glossary/html_color_codes">HTML color codes</a></li><li><a href="/en-US/docs/Glossary/HTML5">HTML5</a></li><li><a href="/en-US/docs/Glossary/HTTP">HTTP</a></li><li><a href="/en-US/docs/Glossary/HTTP_Content">HTTP Content</a></li><li><a href="/en-US/docs/Glossary/HTTP_header">HTTP header</a></li><li><a href="/en-US/docs/Glossary/HTTP_2">HTTP/2</a></li><li><a href="/en-US/docs/Glossary/HTTP_3">HTTP/3</a></li><li><a href="/en-US/docs/Glossary/HTTPS">HTTPS</a></li><li><a href="/en-US/docs/Glossary/HTTPS_RR">HTTPS RR</a></li><li><a href="/en-US/docs/Glossary/Hyperlink">Hyperlink</a></li><li><a href="/en-US/docs/Glossary/Hypertext">Hypertext</a></li><li><a href="/en-US/docs/Glossary/IANA">IANA</a></li><li><a href="/en-US/docs/Glossary/ICANN">ICANN</a></li><li><a href="/en-US/docs/Glossary/ICE">ICE</a></li><li><a href="/en-US/docs/Glossary/IDE">IDE</a></li><li><a href="/en-US/docs/Glossary/Idempotent">Idempotent</a></li><li><a href="/en-US/docs/Glossary/Identifier">Identifier</a></li><li><a href="/en-US/docs/Glossary/Identity_provider">Identity provider (IdP)</a></li><li><a href="/en-US/docs/Glossary/IDL">IDL</a></li><li><a href="/en-US/docs/Glossary/IETF">IETF</a></li><li><a href="/en-US/docs/Glossary/IIFE">IIFE</a></li><li><a href="/en-US/docs/Glossary/IMAP">IMAP</a></li><li><a href="/en-US/docs/Glossary/Immutable">Immutable</a></li><li><a href="/en-US/docs/Glossary/IndexedDB">IndexedDB</a></li><li><a href="/en-US/docs/Glossary/Information_architecture">Information architecture</a></li><li><a href="/en-US/docs/Glossary/Inheritance">Inheritance</a></li><li><a href="/en-US/docs/Glossary/Ink_overflow">Ink overflow</a></li><li><a href="/en-US/docs/Glossary/Inline-level_content">Inline-level content</a></li><li><a href="/en-US/docs/Glossary/Input_method_editor">Input method editor</a></li><li><a href="/en-US/docs/Glossary/Inset_properties">Inset properties</a></li><li><a href="/en-US/docs/Glossary/Instance">Instance</a></li><li><a href="/en-US/docs/Glossary/Interaction_to_next_paint">Interaction to Next Paint (INP)</a></li><li><a href="/en-US/docs/Glossary/Internationalization">Internationalization (i18n)</a></li><li><a href="/en-US/docs/Glossary/Internet">Internet</a></li><li><a href="/en-US/docs/Glossary/Interpolation">Interpolation</a></li><li><a href="/en-US/docs/Glossary/Intrinsic_Size">Intrinsic size</a></li><li><a href="/en-US/docs/Glossary/IP_Address">IP Address</a></li><li><a href="/en-US/docs/Glossary/IPv4">IPv4</a></li><li><a href="/en-US/docs/Glossary/IPv6">IPv6</a></li><li><a href="/en-US/docs/Glossary/IRC">IRC</a></li><li><a href="/en-US/docs/Glossary/ISO">ISO</a></li><li><a href="/en-US/docs/Glossary/ISP">ISP</a></li><li><a href="/en-US/docs/Glossary/ITU">ITU</a></li><li><a href="/en-US/docs/Glossary/Jank">Jank</a></li><li><a href="/en-US/docs/Glossary/Java">Java</a></li><li><a href="/en-US/docs/Glossary/JavaScript">JavaScript</a></li><li><a href="/en-US/docs/Glossary/Jitter">Jitter</a></li><li><a href="/en-US/docs/Glossary/JPEG">JPEG</a></li><li><a href="/en-US/docs/Glossary/JSON">JSON</a></li><li><a href="/en-US/docs/Glossary/JSON_type_representation">JSON type representation</a></li><li><a href="/en-US/docs/Glossary/Kebab_case">Kebab case</a></li><li><a href="/en-US/docs/Glossary/Key">Key</a></li><li><a href="/en-US/docs/Glossary/Keyword">Keyword</a></li><li><a href="/en-US/docs/Glossary/Largest_contentful_paint">Largest Contentful Paint (LCP)</a></li><li><a href="/en-US/docs/Glossary/Latency">Latency</a></li><li><a href="/en-US/docs/Glossary/Layout_viewport">Layout viewport</a></li><li><a href="/en-US/docs/Glossary/Lazy_load">Lazy load</a></li><li><a href="/en-US/docs/Glossary/LGPL">LGPL</a></li><li><a href="/en-US/docs/Glossary/Ligature">Ligature</a></li><li><a href="/en-US/docs/Glossary/Literal">Literal</a></li><li><a href="/en-US/docs/Glossary/Local_scope">Local scope</a></li><li><a href="/en-US/docs/Glossary/Local_variable">Local variable</a></li><li><a href="/en-US/docs/Glossary/Locale">Locale</a></li><li><a href="/en-US/docs/Glossary/Localization">Localization</a></li><li><a href="/en-US/docs/Glossary/Logical_properties">Logical properties</a></li><li><a href="/en-US/docs/Glossary/Long_task">Long task</a></li><li><a href="/en-US/docs/Glossary/Loop">Loop</a></li><li><a href="/en-US/docs/Glossary/Lossless_compression">Lossless compression</a></li><li><a href="/en-US/docs/Glossary/Lossy_compression">Lossy compression</a></li><li><a href="/en-US/docs/Glossary/LTR">LTR (Left To Right)</a></li><li><a href="/en-US/docs/Glossary/Main_Axis">Main Axis</a></li><li><a href="/en-US/docs/Glossary/Main_thread">Main thread</a></li><li><a href="/en-US/docs/Glossary/Markup">Markup</a></li><li><a href="/en-US/docs/Glossary/MathML">MathML</a></li><li><a href="/en-US/docs/Glossary/Media">Media</a></li><li><a href="/en-US/docs/Glossary/Media_query">Media query</a></li><li><a href="/en-US/docs/Glossary/Metadata">Metadata</a></li><li><a href="/en-US/docs/Glossary/Method">Method</a></li><li><a href="/en-US/docs/Glossary/Microsoft_Edge">Microsoft Edge</a></li><li><a href="/en-US/docs/Glossary/Microsoft_Internet_Explorer">Microsoft Internet Explorer</a></li><li><a href="/en-US/docs/Glossary/Middleware">Middleware</a></li><li><a href="/en-US/docs/Glossary/MIME">MIME</a></li><li><a href="/en-US/docs/Glossary/MIME_type">MIME type</a></li><li><a href="/en-US/docs/Glossary/Minification">Minification</a></li><li><a href="/en-US/docs/Glossary/MitM">MitM</a></li><li><a href="/en-US/docs/Glossary/Mixin">Mixin</a></li><li><a href="/en-US/docs/Glossary/Mobile_First">Mobile First</a></li><li><a href="/en-US/docs/Glossary/Modem">Modem</a></li><li><a href="/en-US/docs/Glossary/Modularity">Modularity</a></li><li><a href="/en-US/docs/Glossary/Mozilla_Firefox">Mozilla Firefox</a></li><li><a href="/en-US/docs/Glossary/Mutable">Mutable</a></li><li><a href="/en-US/docs/Glossary/MVC">MVC</a></li><li><a href="/en-US/docs/Glossary/Namespace">Namespace</a></li><li><a href="/en-US/docs/Glossary/NaN">NaN</a></li><li><a href="/en-US/docs/Glossary/NAT">NAT</a></li><li><a href="/en-US/docs/Glossary/Native">Native</a></li><li><a href="/en-US/docs/Glossary/Navigation_directive">Navigation directive</a></li><li><a href="/en-US/docs/Glossary/Netscape_Navigator">Netscape Navigator</a></li><li><a href="/en-US/docs/Glossary/Network_throttling">Network throttling</a></li><li><a href="/en-US/docs/Glossary/NNTP">NNTP</a></li><li><a href="/en-US/docs/Glossary/Node">Node</a></li><li><a href="/en-US/docs/Glossary/Node.js">Node.js</a></li><li><a href="/en-US/docs/Glossary/Non-normative">Non-normative</a></li><li><a href="/en-US/docs/Glossary/Normative">Normative</a></li><li><a href="/en-US/docs/Glossary/Null">Null</a></li><li><a href="/en-US/docs/Glossary/Nullish">Nullish value</a></li><li><a href="/en-US/docs/Glossary/Number">Number</a></li><li><a href="/en-US/docs/Glossary/Object">Object</a></li><li><a href="/en-US/docs/Glossary/Object_reference">Object reference</a></li><li><a href="/en-US/docs/Glossary/OOP">OOP</a></li><li><a href="/en-US/docs/Glossary/OpenGL">OpenGL</a></li><li><a href="/en-US/docs/Glossary/OpenSSL">OpenSSL</a></li><li><a href="/en-US/docs/Glossary/Opera_Browser">Opera Browser</a></li><li><a href="/en-US/docs/Glossary/Operand">Operand</a></li><li><a href="/en-US/docs/Glossary/Operator">Operator</a></li><li><a href="/en-US/docs/Glossary/Origin">Origin</a></li><li><a href="/en-US/docs/Glossary/OTA">OTA</a></li><li><a href="/en-US/docs/Glossary/OWASP">OWASP</a></li><li><a href="/en-US/docs/Glossary/P2P">P2P</a></li><li><a href="/en-US/docs/Glossary/PAC">PAC</a></li><li><a href="/en-US/docs/Glossary/Packet">Packet</a></li><li><a href="/en-US/docs/Glossary/Page_load_time">Page load time</a></li><li><a href="/en-US/docs/Glossary/Page_prediction">Page prediction</a></li><li><a href="/en-US/docs/Glossary/Parameter">Parameter</a></li><li><a href="/en-US/docs/Glossary/Parent_object">Parent object</a></li><li><a href="/en-US/docs/Glossary/Parse">Parse</a></li><li><a href="/en-US/docs/Glossary/Parser">Parser</a></li><li><a href="/en-US/docs/Glossary/Payload_body">Payload body</a></li><li><a href="/en-US/docs/Glossary/Payload_header">Payload header</a></li><li><a href="/en-US/docs/Glossary/PDF">PDF</a></li><li><a href="/en-US/docs/Glossary/Perceived_performance">Perceived performance</a></li><li><a href="/en-US/docs/Glossary/Percent-encoding">Percent-encoding</a></li><li><a href="/en-US/docs/Glossary/PHP">PHP</a></li><li><a href="/en-US/docs/Glossary/Physical_properties">Physical properties</a></li><li><a href="/en-US/docs/Glossary/Pixel">Pixel</a></li><li><a href="/en-US/docs/Glossary/Placeholder_names">Placeholder names</a></li><li><a href="/en-US/docs/Glossary/Plaintext">Plaintext</a></li><li><a href="/en-US/docs/Glossary/Plugin">Plugin</a></li><li><a href="/en-US/docs/Glossary/PNG">PNG</a></li><li><a href="/en-US/docs/Glossary/Polyfill">Polyfill</a></li><li><a href="/en-US/docs/Glossary/Polymorphism">Polymorphism</a></li><li><a href="/en-US/docs/Glossary/POP">POP3</a></li><li><a href="/en-US/docs/Glossary/Port">Port</a></li><li><a href="/en-US/docs/Glossary/Prefetch">Prefetch</a></li><li><a href="/en-US/docs/Glossary/Preflight_request">Preflight request</a></li><li><a href="/en-US/docs/Glossary/Prerender">Prerender</a></li><li><a href="/en-US/docs/Glossary/Presto">Presto</a></li><li><a href="/en-US/docs/Glossary/Primitive">Primitive</a></li><li><a href="/en-US/docs/Glossary/Privileged">Privileged</a></li><li><a href="/en-US/docs/Glossary/Privileged_code">Privileged code</a></li><li><a href="/en-US/docs/Glossary/Progressive_Enhancement">Progressive Enhancement</a></li><li><a href="/en-US/docs/Glossary/Progressive_web_apps">Progressive web apps</a></li><li><a href="/en-US/docs/Glossary/Promise">Promise</a></li><li><a href="/en-US/docs/Glossary/Property">Property</a></li><li><a href="/en-US/docs/Glossary/Protocol">Protocol</a></li><li><a href="/en-US/docs/Glossary/Prototype">Prototype</a></li><li><a href="/en-US/docs/Glossary/Prototype-based_programming">Prototype-based programming</a></li><li><a href="/en-US/docs/Glossary/Proxy_server">Proxy server</a></li><li><a href="/en-US/docs/Glossary/Pseudo-class">Pseudo-class</a></li><li><a href="/en-US/docs/Glossary/Pseudo-element">Pseudo-element</a></li><li><a href="/en-US/docs/Glossary/Pseudocode">Pseudocode</a></li><li><a href="/en-US/docs/Glossary/Public-key_cryptography">Public-key cryptography</a></li><li><a href="/en-US/docs/Glossary/Python">Python</a></li><li><a href="/en-US/docs/Glossary/Quality_values">Quality values</a></li><li><a href="/en-US/docs/Glossary/Quaternion">Quaternion</a></li><li><a href="/en-US/docs/Glossary/QUIC">QUIC</a></li><li><a href="/en-US/docs/Glossary/RAIL">RAIL</a></li><li><a href="/en-US/docs/Glossary/RNG">Random Number Generator</a></li><li><a href="/en-US/docs/Glossary/Raster_image">Raster image</a></li><li><a href="/en-US/docs/Glossary/Rate_limit">Rate limit</a></li><li><a href="/en-US/docs/Glossary/RDF">RDF</a></li><li><a href="/en-US/docs/Glossary/Real_User_Monitoring">Real User Monitoring (RUM)</a></li><li><a href="/en-US/docs/Glossary/Recursion">Recursion</a></li><li><a href="/en-US/docs/Glossary/Reflow">Reflow</a></li><li><a href="/en-US/docs/Glossary/Regular_expression">Regular expression</a></li><li><a href="/en-US/docs/Glossary/Relying_party">Relying party</a></li><li><a href="/en-US/docs/Glossary/Render_blocking">Render-blocking</a></li><li><a href="/en-US/docs/Glossary/Repaint">Repaint</a></li><li><a href="/en-US/docs/Glossary/Replay_attack">Replay attack</a></li><li><a href="/en-US/docs/Glossary/Repo">Repo</a></li><li><a href="/en-US/docs/Glossary/Reporting_directive">Reporting directive</a></li><li><a href="/en-US/docs/Glossary/Representation_header">Representation header</a></li><li><a href="/en-US/docs/Glossary/Request_header">Request header</a></li><li><a href="/en-US/docs/Glossary/Resource_Timing">Resource Timing</a></li><li><a href="/en-US/docs/Glossary/Response_header">Response header</a></li><li><a href="/en-US/docs/Glossary/Responsive_web_design">Responsive web design</a></li><li><a href="/en-US/docs/Glossary/REST">REST</a></li><li><a href="/en-US/docs/Glossary/RGB">RGB</a></li><li><a href="/en-US/docs/Glossary/RIL">RIL</a></li><li><a href="/en-US/docs/Glossary/Robots.txt">Robots.txt</a></li><li><a href="/en-US/docs/Glossary/Round_Trip_Time">Round Trip Time (RTT)</a></li><li><a href="/en-US/docs/Glossary/Router">Router</a></li><li><a href="/en-US/docs/Glossary/RSS">RSS</a></li><li><a href="/en-US/docs/Glossary/Rsync">Rsync</a></li><li><a href="/en-US/docs/Glossary/RTCP">RTCP (RTP Control Protocol)</a></li><li><a href="/en-US/docs/Glossary/RTF">RTF</a></li><li><a href="/en-US/docs/Glossary/RTL">RTL (Right to Left)</a></li><li><a href="/en-US/docs/Glossary/RTP">RTP (Real-time Transport Protocol) and SRTP (Secure RTP)</a></li><li><a href="/en-US/docs/Glossary/RTSP">RTSP: Real-time streaming protocol</a></li><li><a href="/en-US/docs/Glossary/Ruby">Ruby</a></li><li><a href="/en-US/docs/Glossary/Safe">Safe</a></li><li><a href="/en-US/docs/Glossary/Salt">Salt</a></li><li><a href="/en-US/docs/Glossary/Same-origin_policy">Same-origin policy</a></li><li><a href="/en-US/docs/Glossary/SCM">SCM</a></li><li><a href="/en-US/docs/Glossary/Scope">Scope</a></li><li><a href="/en-US/docs/Glossary/Screen_reader">Screen reader</a></li><li><a href="/en-US/docs/Glossary/Script-supporting_element">Script-supporting element</a></li><li><a href="/en-US/docs/Glossary/Scroll_boundary">Scroll boundary</a></li><li><a href="/en-US/docs/Glossary/Scroll_chaining">Scroll chaining</a></li><li><a href="/en-US/docs/Glossary/Scroll_container">Scroll container</a></li><li><a href="/en-US/docs/Glossary/Scroll_snap">Scroll snap</a></li><li><a href="/en-US/docs/Glossary/SCTP">SCTP</a></li><li><a href="/en-US/docs/Glossary/SDK">SDK (Software Development Kit)</a></li><li><a href="/en-US/docs/Glossary/SDP">SDP</a></li><li><a href="/en-US/docs/Glossary/Search_engine">Search engine</a></li><li><a href="/en-US/docs/Glossary/Secure_Context">Secure Context</a></li><li><a href="/en-US/docs/Glossary/SSL">Secure Sockets Layer (SSL)</a></li><li><a href="/en-US/docs/Glossary/CSS_Selector">Selector (CSS)</a></li><li><a href="/en-US/docs/Glossary/Self-Executing_Anonymous_Function">Self-Executing Anonymous Function</a></li><li><a href="/en-US/docs/Glossary/Semantics">Semantics</a></li><li><a href="/en-US/docs/Glossary/SEO">SEO</a></li><li><a href="/en-US/docs/Glossary/Serializable_object">Serializable object</a></li><li><a href="/en-US/docs/Glossary/Serialization">Serialization</a></li><li><a href="/en-US/docs/Glossary/Server">Server</a></li><li><a href="/en-US/docs/Glossary/Server_Timing">Server Timing</a></li><li><a href="/en-US/docs/Glossary/Session_Hijacking">Session Hijacking</a></li><li><a href="/en-US/docs/Glossary/SGML">SGML</a></li><li><a href="/en-US/docs/Glossary/Shadow_tree">Shadow tree</a></li><li><a href="/en-US/docs/Glossary/Shallow_copy">Shallow copy</a></li><li><a href="/en-US/docs/Glossary/Shim">Shim</a></li><li><a href="/en-US/docs/Glossary/Signature">Signature</a></li><li><a href="/en-US/docs/Glossary/SIMD">SIMD</a></li><li><a href="/en-US/docs/Glossary/SISD">SISD</a></li><li><a href="/en-US/docs/Glossary/Site">Site</a></li><li><a href="/en-US/docs/Glossary/Site_map">Site map</a></li><li><a href="/en-US/docs/Glossary/SLD">SLD</a></li><li><a href="/en-US/docs/Glossary/Sloppy_mode">Sloppy mode</a></li><li><a href="/en-US/docs/Glossary/Slug">Slug</a></li><li><a href="/en-US/docs/Glossary/Smoke_Test">Smoke Test</a></li><li><a href="/en-US/docs/Glossary/SMPTE">SMPTE (Society of Motion Picture and Television Engineers)</a></li><li><a href="/en-US/docs/Glossary/SMTP">SMTP</a></li><li><a href="/en-US/docs/Glossary/Snake_case">Snake case</a></li><li><a href="/en-US/docs/Glossary/Snap_positions">Snap positions</a></li><li><a href="/en-US/docs/Glossary/SOAP">SOAP</a></li><li><a href="/en-US/docs/Glossary/SPA">SPA (Single-page application)</a></li><li><a href="/en-US/docs/Glossary/Specification">Specification</a></li><li><a href="/en-US/docs/Glossary/Speculative_parsing">Speculative parsing</a></li><li><a href="/en-US/docs/Glossary/Speed_index">Speed index</a></li><li><a href="/en-US/docs/Glossary/SQL">SQL</a></li><li><a href="/en-US/docs/Glossary/SQL_Injection">SQL Injection</a></li><li><a href="/en-US/docs/Glossary/SRI">SRI</a></li><li><a href="/en-US/docs/Glossary/Stacking_context">Stacking context</a></li><li><a href="/en-US/docs/Glossary/State_machine">State machine</a></li><li><a href="/en-US/docs/Glossary/Statement">Statement</a></li><li><a href="/en-US/docs/Glossary/Static_method">Static method</a></li><li><a href="/en-US/docs/Glossary/SSG">Static site generator (SSG)</a></li><li><a href="/en-US/docs/Glossary/Static_typing">Static typing</a></li><li><a href="/en-US/docs/Glossary/Sticky_activation">Sticky activation</a></li><li><a href="/en-US/docs/Glossary/Strict_mode">Strict mode</a></li><li><a href="/en-US/docs/Glossary/String">String</a></li><li><a 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Box</a></li><li><a href="/en-US/docs/Glossary/Tag">Tag</a></li><li><a href="/en-US/docs/Glossary/TCP">TCP</a></li><li><a href="/en-US/docs/Glossary/TCP_handshake">TCP handshake</a></li><li><a href="/en-US/docs/Glossary/TCP_slow_start">TCP slow start</a></li><li><a href="/en-US/docs/Glossary/Telnet">Telnet</a></li><li><a href="/en-US/docs/Glossary/Texel">Texel</a></li><li><a href="/en-US/docs/Glossary/Khronos">The Khronos Group</a></li><li><a href="/en-US/docs/Glossary/Thread">Thread</a></li><li><a href="/en-US/docs/Glossary/Three_js">Three js</a></li><li><a href="/en-US/docs/Glossary/Throttle">Throttle</a></li><li><a href="/en-US/docs/Glossary/Time_to_first_byte">Time to first byte</a></li><li><a href="/en-US/docs/Glossary/Time_to_interactive">Time to interactive</a></li><li><a href="/en-US/docs/Glossary/TLD">TLD</a></li><li><a href="/en-US/docs/Glossary/TOFU">TOFU</a></li><li><a href="/en-US/docs/Glossary/Top_layer">Top layer</a></li><li><a href="/en-US/docs/Glossary/Transient_activation">Transient activation</a></li><li><a href="/en-US/docs/Glossary/TLS">Transport Layer Security (TLS)</a></li><li><a href="/en-US/docs/Glossary/Tree_shaking">Tree shaking</a></li><li><a href="/en-US/docs/Glossary/Trident">Trident</a></li><li><a href="/en-US/docs/Glossary/Truthy">Truthy</a></li><li><a href="/en-US/docs/Glossary/TTL">TTL</a></li><li><a href="/en-US/docs/Glossary/TURN">TURN</a></li><li><a href="/en-US/docs/Glossary/Type">Type</a></li><li><a href="/en-US/docs/Glossary/Type_coercion">Type coercion</a></li><li><a href="/en-US/docs/Glossary/Type_Conversion">Type conversion</a></li><li><a href="/en-US/docs/Glossary/TypeScript">TypeScript</a></li><li><a href="/en-US/docs/Glossary/UAAG">UAAG</a></li><li><a href="/en-US/docs/Glossary/UDP">UDP (User Datagram Protocol)</a></li><li><a href="/en-US/docs/Glossary/UI">UI</a></li><li><a href="/en-US/docs/Glossary/Undefined">Undefined</a></li><li><a href="/en-US/docs/Glossary/Unicode">Unicode</a></li><li><a href="/en-US/docs/Glossary/Unix_time">Unix time</a></li><li><a href="/en-US/docs/Glossary/URI">URI</a></li><li><a href="/en-US/docs/Glossary/URL">URL</a></li><li><a href="/en-US/docs/Glossary/URN">URN</a></li><li><a href="/en-US/docs/Glossary/Usenet">Usenet</a></li><li><a href="/en-US/docs/Glossary/User_agent">User agent</a></li><li><a href="/en-US/docs/Glossary/UTF-8">UTF-8</a></li><li><a href="/en-US/docs/Glossary/UUID">UUID</a></li><li><a href="/en-US/docs/Glossary/UX">UX</a></li><li><a href="/en-US/docs/Glossary/Validator">Validator</a></li><li><a href="/en-US/docs/Glossary/Value">Value</a></li><li><a href="/en-US/docs/Glossary/Variable">Variable</a></li><li><a href="/en-US/docs/Glossary/Vendor_Prefix">Vendor Prefix</a></li><li><a href="/en-US/docs/Glossary/Viewport">Viewport</a></li><li><a href="/en-US/docs/Glossary/Visual_Viewport">Visual Viewport</a></li><li><a href="/en-US/docs/Glossary/Void_element">Void element</a></li><li><a href="/en-US/docs/Glossary/VoIP">VoIP</a></li><li><a href="/en-US/docs/Glossary/W3C">W3C</a></li><li><a href="/en-US/docs/Glossary/WAI">WAI</a></li><li><a href="/en-US/docs/Glossary/WCAG">WCAG</a></li><li><a href="/en-US/docs/Glossary/Web_performance">Web performance</a></li><li><a href="/en-US/docs/Glossary/Web_server">Web server</a></li><li><a href="/en-US/docs/Glossary/Web_standards">Web standards</a></li><li><a href="/en-US/docs/Glossary/WebAssembly">WebAssembly</a></li><li><a href="/en-US/docs/Glossary/WebDAV">WebDAV</a></li><li><a href="/en-US/docs/Glossary/WebExtensions">WebExtensions</a></li><li><a href="/en-US/docs/Glossary/WebGL">WebGL</a></li><li><a href="/en-US/docs/Glossary/WebIDL">WebIDL</a></li><li><a href="/en-US/docs/Glossary/WebKit">WebKit</a></li><li><a href="/en-US/docs/Glossary/WebM">WebM</a></li><li><a href="/en-US/docs/Glossary/WebP">WebP</a></li><li><a href="/en-US/docs/Glossary/WebRTC">WebRTC</a></li><li><a href="/en-US/docs/Glossary/WebSockets">WebSockets</a></li><li><a href="/en-US/docs/Glossary/WebVTT">WebVTT</a></li><li><a href="/en-US/docs/Glossary/WHATWG">WHATWG</a></li><li><a href="/en-US/docs/Glossary/Whitespace">Whitespace</a></li><li><a href="/en-US/docs/Glossary/WindowProxy">WindowProxy</a></li><li><a href="/en-US/docs/Glossary/World_Wide_Web">World Wide Web</a></li><li><a href="/en-US/docs/Glossary/Wrapper">Wrapper</a></li><li><a href="/en-US/docs/Glossary/XForms">XForms</a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Glossary/XHTML">XHTML</a></li><li><a href="/en-US/docs/Glossary/XInclude">XInclude</a></li><li><a href="/en-US/docs/Glossary/XLink">XLink</a></li><li><a href="/en-US/docs/Glossary/XML">XML</a></li><li><a href="/en-US/docs/Glossary/XMLHttpRequest">XMLHttpRequest (XHR)</a></li><li><a href="/en-US/docs/Glossary/XPath">XPath</a></li><li><a href="/en-US/docs/Glossary/XQuery">XQuery</a></li><li><a href="/en-US/docs/Glossary/XSLT">XSLT</a></li><li><a href="/en-US/docs/Glossary/Zstandard_compression">Zstandard compression</a></li></ol> </li> </ol> </div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>Cacheable</h1></header><div class="section-content"><p>A <strong>cacheable</strong> response is an HTTP response that can be cached, that is stored to be retrieved and used later, saving a new request to the server. Not all HTTP responses can be cached; these are the constraints for an HTTP response to be cacheable:</p> <ul> <li>The method used in the request is <em>cacheable</em>, that is either a <a href="/en-US/docs/Web/HTTP/Methods/GET"><code>GET</code></a> or a <a href="/en-US/docs/Web/HTTP/Methods/HEAD"><code>HEAD</code></a> method. A response to a <a href="/en-US/docs/Web/HTTP/Methods/POST"><code>POST</code></a> or <a href="/en-US/docs/Web/HTTP/Methods/PATCH"><code>PATCH</code></a> request can also be cached if freshness is indicated and the <a href="/en-US/docs/Web/HTTP/Headers/Content-Location"><code>Content-Location</code></a> header is set, but this is rarely implemented. For example, Firefox does not support it (<a href="https://bugzil.la/109553" class="external" target="_blank">Firefox bug 109553</a>). Other methods, like <a href="/en-US/docs/Web/HTTP/Methods/PUT"><code>PUT</code></a> or <a href="/en-US/docs/Web/HTTP/Methods/DELETE"><code>DELETE</code></a> are not cacheable and their result cannot be cached.</li> <li>The status code of the response is <em>known</em> by the application caching, and is <em>cacheable</em>. The following status codes are cacheable: <a href="/en-US/docs/Web/HTTP/Status/200"><code>200</code></a>, <a href="/en-US/docs/Web/HTTP/Status/203"><code>203</code></a>, <a href="/en-US/docs/Web/HTTP/Status/204"><code>204</code></a>, <a href="/en-US/docs/Web/HTTP/Status/206"><code>206</code></a>, <a href="/en-US/docs/Web/HTTP/Status/300"><code>300</code></a>, <a href="/en-US/docs/Web/HTTP/Status/301"><code>301</code></a>, <a href="/en-US/docs/Web/HTTP/Status/404"><code>404</code></a>, <a href="/en-US/docs/Web/HTTP/Status/405"><code>405</code></a>, <a href="/en-US/docs/Web/HTTP/Status/410"><code>410</code></a>, <a href="/en-US/docs/Web/HTTP/Status/414"><code>414</code></a>, and <a href="/en-US/docs/Web/HTTP/Status/501"><code>501</code></a>.</li> <li>There are no specific headers in the response, like <a href="/en-US/docs/Web/HTTP/Headers/Cache-Control"><code>Cache-Control</code></a>, with values that would prohibit caching.</li> </ul> <p>Note that some requests with non-cacheable responses to a specific URI may invalidate previously cached responses from the same URI. For example, a <a href="/en-US/docs/Web/HTTP/Methods/PUT"><code>PUT</code></a> to <code>/pageX.html</code> will invalidate all cached responses to <a href="/en-US/docs/Web/HTTP/Methods/GET"><code>GET</code></a> or <a href="/en-US/docs/Web/HTTP/Methods/HEAD"><code>HEAD</code></a> requests to <code>/pageX.html</code>.</p> <p>When both the method of the request and the status of the response are cacheable, the response to the request can be cached:</p> <div class="code-example"><div class="example-header"><span class="language-name">http</span></div><pre class="brush: http notranslate"><code>GET /pageX.html HTTP/1.1 (…) 200 OK (…) </code></pre></div> <p>The response to a <a href="/en-US/docs/Web/HTTP/Methods/PUT"><code>PUT</code></a> request cannot be cached. Moreover, it invalidates cached data for requests to the same URI using <a href="/en-US/docs/Web/HTTP/Methods/HEAD"><code>HEAD</code></a> or <a href="/en-US/docs/Web/HTTP/Methods/GET"><code>GET</code></a> methods:</p> <div class="code-example"><div class="example-header"><span class="language-name">http</span></div><pre class="brush: http notranslate"><code>PUT /pageX.html HTTP/1.1 (…) 200 OK (…) </code></pre></div> <p>The presence of the <a href="/en-US/docs/Web/HTTP/Headers/Cache-Control"><code>Cache-Control</code></a> header with a particular value in the response can prevent caching:</p> <div class="code-example"><div class="example-header"><span class="language-name">http</span></div><pre class="brush: http notranslate"><code>GET /pageX.html HTTP/1.1 (…) 200 OK Cache-Control: no-cache (…) </code></pre></div></div><section aria-labelledby="see_also"><h2 id="see_also"><a href="#see_also">See also</a></h2><div class="section-content"><ul> <li>Details about <a href="https://httpwg.org/specs/rfc9110.html#rfc.section.9.2.3" class="external" target="_blank">methods and caching</a> are provided in the HTTP specification.</li> <li>Description of common cacheable methods: <a href="/en-US/docs/Web/HTTP/Methods/GET"><code>GET</code></a>, <a href="/en-US/docs/Web/HTTP/Methods/HEAD"><code>HEAD</code></a></li> <li>Description of common non-cacheable methods: <a href="/en-US/docs/Web/HTTP/Methods/PUT"><code>PUT</code></a>, <a href="/en-US/docs/Web/HTTP/Methods/DELETE"><code>DELETE</code></a>, often <a href="/en-US/docs/Web/HTTP/Methods/POST"><code>POST</code></a></li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 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href=\"/en-US/docs/Glossary/Browsing_context\">Browsing context</a></li><li><a href=\"/en-US/docs/Glossary/Buffer\">Buffer</a></li><li><a href=\"/en-US/docs/Glossary/Cache\">Cache</a></li><li><em><a href=\"/en-US/docs/Glossary/Cacheable\" aria-current=\"page\">Cacheable</a></em></li><li><a href=\"/en-US/docs/Glossary/CalDAV\">CalDAV</a></li><li><a href=\"/en-US/docs/Glossary/Call_stack\">Call stack</a></li><li><a href=\"/en-US/docs/Glossary/Callback_function\">Callback function</a></li><li><a href=\"/en-US/docs/Glossary/Camel_case\">Camel case</a></li><li><a href=\"/en-US/docs/Glossary/Canonical_order\">Canonical order</a></li><li><a href=\"/en-US/docs/Glossary/Canvas\">Canvas</a></li><li><a href=\"/en-US/docs/Glossary/Card_sorting\">Card sorting</a></li><li><a href=\"/en-US/docs/Glossary/CardDAV\">CardDAV</a></li><li><a href=\"/en-US/docs/Glossary/Caret\">Caret</a></li><li><a href=\"/en-US/docs/Glossary/CDN\">CDN</a></li><li><a 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href=\"/en-US/docs/Glossary/CRLF\">CRLF</a></li><li><a href=\"/en-US/docs/Glossary/Cross_Axis\">Cross Axis</a></li><li><a href=\"/en-US/docs/Glossary/Cross-site_scripting\">Cross-site scripting (XSS)</a></li><li><a href=\"/en-US/docs/Glossary/CRUD\">CRUD</a></li><li><a href=\"/en-US/docs/Glossary/Cryptanalysis\">Cryptanalysis</a></li><li><a href=\"/en-US/docs/Glossary/Cryptographic_hash_function\">Cryptographic hash function</a></li><li><a href=\"/en-US/docs/Glossary/Cryptography\">Cryptography</a></li><li><a href=\"/en-US/docs/Glossary/CSP\">CSP</a></li><li><a href=\"/en-US/docs/Glossary/CSRF\">CSRF</a></li><li><a href=\"/en-US/docs/Glossary/CSS\">CSS</a></li><li><a href=\"/en-US/docs/Glossary/CSSOM\">CSS Object Model (CSSOM)</a></li><li><a href=\"/en-US/docs/Glossary/CSS_pixel\">CSS pixel</a></li><li><a href=\"/en-US/docs/Glossary/CSS_preprocessor\">CSS preprocessor</a></li><li><a href=\"/en-US/docs/Glossary/CLS\">Cumulative Layout Shift (CLS)</a></li><li><a href=\"/en-US/docs/Glossary/Data_structure\">Data structure</a></li><li><a href=\"/en-US/docs/Glossary/Database\">Database</a></li><li><a href=\"/en-US/docs/Glossary/Debounce\">Debounce</a></li><li><a href=\"/en-US/docs/Glossary/Decryption\">Decryption</a></li><li><a href=\"/en-US/docs/Glossary/Deep_copy\">Deep copy</a></li><li><a href=\"/en-US/docs/Glossary/Delta\">Delta</a></li><li><a href=\"/en-US/docs/Glossary/Denial_of_Service\">Denial of Service</a></li><li><a href=\"/en-US/docs/Glossary/Deno\">Deno</a></li><li><a href=\"/en-US/docs/Glossary/CSS_Descriptor\">Descriptor (CSS)</a></li><li><a href=\"/en-US/docs/Glossary/Deserialization\">Deserialization</a></li><li><a href=\"/en-US/docs/Glossary/Developer_Tools\">Developer Tools</a></li><li><a href=\"/en-US/docs/Glossary/Digest\">Digest</a></li><li><a href=\"/en-US/docs/Glossary/Digital_certificate\">Digital certificate</a></li><li><a href=\"/en-US/docs/Glossary/Digital_signature\">Digital signature</a></li><li><a href=\"/en-US/docs/Glossary/Distributed_Denial_of_Service\">Distributed Denial of Service</a></li><li><a href=\"/en-US/docs/Glossary/DMZ\">DMZ</a></li><li><a href=\"/en-US/docs/Glossary/DNS\">DNS</a></li><li><a href=\"/en-US/docs/Glossary/Doctype\">Doctype</a></li><li><a href=\"/en-US/docs/Glossary/Document_directive\">Document directive</a></li><li><a href=\"/en-US/docs/Glossary/Document_environment\">Document environment</a></li><li><a href=\"/en-US/docs/Glossary/DOM\">DOM (Document Object Model)</a></li><li><a href=\"/en-US/docs/Glossary/Domain\">Domain</a></li><li><a href=\"/en-US/docs/Glossary/Domain_name\">Domain name</a></li><li><a href=\"/en-US/docs/Glossary/Domain_sharding\">Domain sharding</a></li><li><a href=\"/en-US/docs/Glossary/Dominator\">Dominator</a></li><li><a href=\"/en-US/docs/Glossary/DOS_attack\">DoS attack</a></li><li><a href=\"/en-US/docs/Glossary/DSL\">DSL</a></li><li><a href=\"/en-US/docs/Glossary/DTLS\">DTLS (Datagram Transport Layer Security)</a></li><li><a href=\"/en-US/docs/Glossary/DTMF\">DTMF (Dual-Tone Multi-Frequency signaling)</a></li><li><a href=\"/en-US/docs/Glossary/Dynamic_typing\">Dynamic typing</a></li><li><a href=\"/en-US/docs/Glossary/ECMA\">ECMA</a></li><li><a href=\"/en-US/docs/Glossary/ECMAScript\">ECMAScript</a></li><li><a href=\"/en-US/docs/Glossary/Effective_connection_type\">Effective connection type</a></li><li><a href=\"/en-US/docs/Glossary/Element\">Element</a></li><li><a href=\"/en-US/docs/Glossary/Encapsulation\">Encapsulation</a></li><li><a href=\"/en-US/docs/Glossary/Encryption\">Encryption</a></li><li><a href=\"/en-US/docs/Glossary/Endianness\">Endianness</a></li><li><a href=\"/en-US/docs/Glossary/Engine\">Engine</a></li><li><a href=\"/en-US/docs/Glossary/Entity\">Entity</a></li><li><a href=\"/en-US/docs/Glossary/Entity_header\">Entity header</a></li><li><a href=\"/en-US/docs/Glossary/Enumerated\">Enumerated</a></li><li><a href=\"/en-US/docs/Glossary/eTLD\">eTLD</a></li><li><a href=\"/en-US/docs/Glossary/Event\">Event</a></li><li><a href=\"/en-US/docs/Glossary/Exception\">Exception</a></li><li><a href=\"/en-US/docs/Glossary/EXIF\">EXIF</a></li><li><a href=\"/en-US/docs/Glossary/Expando\">Expando</a></li><li><a href=\"/en-US/docs/Glossary/Fallback_Alignment\">Fallback alignment</a></li><li><a href=\"/en-US/docs/Glossary/Falsy\">Falsy</a></li><li><a href=\"/en-US/docs/Glossary/Favicon\">Favicon</a></li><li><a href=\"/en-US/docs/Glossary/Federated_identity\">Federated identity</a></li><li><a href=\"/en-US/docs/Glossary/Fetch_directive\">Fetch directive</a></li><li><a href=\"/en-US/docs/Glossary/Fetch_metadata_request_header\">Fetch metadata request header</a></li><li><a href=\"/en-US/docs/Glossary/Fingerprinting\">Fingerprinting</a></li><li><a href=\"/en-US/docs/Glossary/Firefox_OS\">Firefox OS</a></li><li><a href=\"/en-US/docs/Glossary/Firewall\">Firewall</a></li><li><a href=\"/en-US/docs/Glossary/First_contentful_paint\">First Contentful Paint (FCP)</a></li><li><a href=\"/en-US/docs/Glossary/First_CPU_idle\">First CPU idle</a></li><li><a href=\"/en-US/docs/Glossary/First_input_delay\">First Input Delay (FID)</a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Glossary/First_meaningful_paint\">First Meaningful Paint (FMP)</a></li><li><a href=\"/en-US/docs/Glossary/First_paint\">First Paint (FP)</a></li><li><a href=\"/en-US/docs/Glossary/First-class_Function\">First-class Function</a></li><li><a href=\"/en-US/docs/Glossary/Flex\">Flex</a></li><li><a href=\"/en-US/docs/Glossary/Flex_Container\">Flex Container</a></li><li><a href=\"/en-US/docs/Glossary/Flex_Item\">Flex Item</a></li><li><a href=\"/en-US/docs/Glossary/Flexbox\">Flexbox</a></li><li><a href=\"/en-US/docs/Glossary/Flow_relative_values\">Flow relative values</a></li><li><a href=\"/en-US/docs/Glossary/Forbidden_header_name\">Forbidden header name</a></li><li><a href=\"/en-US/docs/Glossary/Forbidden_response_header_name\">Forbidden response header name</a></li><li><a href=\"/en-US/docs/Glossary/Fork\">Fork</a></li><li><a href=\"/en-US/docs/Glossary/Fragmentainer\">Fragmentainer</a></li><li><a href=\"/en-US/docs/Glossary/FPS\">Frame rate (FPS)</a></li><li><a href=\"/en-US/docs/Glossary/FTP\">FTP</a></li><li><a href=\"/en-US/docs/Glossary/FTU\">FTU</a></li><li><a href=\"/en-US/docs/Glossary/Function\">Function</a></li><li><a href=\"/en-US/docs/Glossary/Fuzzing\">Fuzz testing</a></li><li><a href=\"/en-US/docs/Glossary/Gamut\">Gamut</a></li><li><a href=\"/en-US/docs/Glossary/Garbage_collection\">Garbage collection</a></li><li><a href=\"/en-US/docs/Glossary/Gecko\">Gecko</a></li><li><a href=\"/en-US/docs/Glossary/General_header\">General header</a></li><li><a href=\"/en-US/docs/Glossary/GIF\">GIF</a></li><li><a href=\"/en-US/docs/Glossary/Git\">Git</a></li><li><a href=\"/en-US/docs/Glossary/Global_object\">Global object</a></li><li><a href=\"/en-US/docs/Glossary/Global_scope\">Global scope</a></li><li><a href=\"/en-US/docs/Glossary/Global_variable\">Global variable</a></li><li><a href=\"/en-US/docs/Glossary/Glyph\">Glyph</a></li><li><a href=\"/en-US/docs/Glossary/Google_Chrome\">Google Chrome</a></li><li><a href=\"/en-US/docs/Glossary/GPL\">GPL</a></li><li><a href=\"/en-US/docs/Glossary/GPU\">GPU</a></li><li><a href=\"/en-US/docs/Glossary/Graceful_degradation\">Graceful degradation</a></li><li><a href=\"/en-US/docs/Glossary/Grid\">Grid</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Areas\">Grid Areas</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Axis\">Grid Axis</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Cell\">Grid Cell</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Column\">Grid Column</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Container\">Grid container</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Lines\">Grid Lines</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Row\">Grid Row</a></li><li><a href=\"/en-US/docs/Glossary/Grid_Tracks\">Grid Tracks</a></li><li><a href=\"/en-US/docs/Glossary/Gutters\">Gutters</a></li><li><a href=\"/en-US/docs/Glossary/gzip_compression\">gzip compression</a></li><li><a href=\"/en-US/docs/Glossary/Hash\">Hash</a></li><li><a href=\"/en-US/docs/Glossary/Head\">Head</a></li><li><a href=\"/en-US/docs/Glossary/High-level_programming_language\">High-level programming language</a></li><li><a href=\"/en-US/docs/Glossary/HMAC\">HMAC</a></li><li><a href=\"/en-US/docs/Glossary/Hoisting\">Hoisting</a></li><li><a href=\"/en-US/docs/Glossary/Host\">Host</a></li><li><a href=\"/en-US/docs/Glossary/Hotlink\">Hotlink</a></li><li><a href=\"/en-US/docs/Glossary/Houdini\">Houdini</a></li><li><a href=\"/en-US/docs/Glossary/HPKP\">HPKP</a></li><li><a href=\"/en-US/docs/Glossary/HSTS\">HSTS</a></li><li><a href=\"/en-US/docs/Glossary/HTML\">HTML</a></li><li><a href=\"/en-US/docs/Glossary/html_color_codes\">HTML color codes</a></li><li><a href=\"/en-US/docs/Glossary/HTML5\">HTML5</a></li><li><a href=\"/en-US/docs/Glossary/HTTP\">HTTP</a></li><li><a href=\"/en-US/docs/Glossary/HTTP_Content\">HTTP Content</a></li><li><a href=\"/en-US/docs/Glossary/HTTP_header\">HTTP header</a></li><li><a href=\"/en-US/docs/Glossary/HTTP_2\">HTTP/2</a></li><li><a href=\"/en-US/docs/Glossary/HTTP_3\">HTTP/3</a></li><li><a href=\"/en-US/docs/Glossary/HTTPS\">HTTPS</a></li><li><a href=\"/en-US/docs/Glossary/HTTPS_RR\">HTTPS RR</a></li><li><a href=\"/en-US/docs/Glossary/Hyperlink\">Hyperlink</a></li><li><a href=\"/en-US/docs/Glossary/Hypertext\">Hypertext</a></li><li><a href=\"/en-US/docs/Glossary/IANA\">IANA</a></li><li><a href=\"/en-US/docs/Glossary/ICANN\">ICANN</a></li><li><a href=\"/en-US/docs/Glossary/ICE\">ICE</a></li><li><a href=\"/en-US/docs/Glossary/IDE\">IDE</a></li><li><a href=\"/en-US/docs/Glossary/Idempotent\">Idempotent</a></li><li><a href=\"/en-US/docs/Glossary/Identifier\">Identifier</a></li><li><a href=\"/en-US/docs/Glossary/Identity_provider\">Identity provider (IdP)</a></li><li><a href=\"/en-US/docs/Glossary/IDL\">IDL</a></li><li><a href=\"/en-US/docs/Glossary/IETF\">IETF</a></li><li><a href=\"/en-US/docs/Glossary/IIFE\">IIFE</a></li><li><a href=\"/en-US/docs/Glossary/IMAP\">IMAP</a></li><li><a href=\"/en-US/docs/Glossary/Immutable\">Immutable</a></li><li><a href=\"/en-US/docs/Glossary/IndexedDB\">IndexedDB</a></li><li><a href=\"/en-US/docs/Glossary/Information_architecture\">Information architecture</a></li><li><a href=\"/en-US/docs/Glossary/Inheritance\">Inheritance</a></li><li><a href=\"/en-US/docs/Glossary/Ink_overflow\">Ink overflow</a></li><li><a href=\"/en-US/docs/Glossary/Inline-level_content\">Inline-level content</a></li><li><a href=\"/en-US/docs/Glossary/Input_method_editor\">Input method editor</a></li><li><a href=\"/en-US/docs/Glossary/Inset_properties\">Inset properties</a></li><li><a href=\"/en-US/docs/Glossary/Instance\">Instance</a></li><li><a href=\"/en-US/docs/Glossary/Interaction_to_next_paint\">Interaction to Next Paint (INP)</a></li><li><a href=\"/en-US/docs/Glossary/Internationalization\">Internationalization (i18n)</a></li><li><a href=\"/en-US/docs/Glossary/Internet\">Internet</a></li><li><a href=\"/en-US/docs/Glossary/Interpolation\">Interpolation</a></li><li><a href=\"/en-US/docs/Glossary/Intrinsic_Size\">Intrinsic size</a></li><li><a href=\"/en-US/docs/Glossary/IP_Address\">IP Address</a></li><li><a href=\"/en-US/docs/Glossary/IPv4\">IPv4</a></li><li><a href=\"/en-US/docs/Glossary/IPv6\">IPv6</a></li><li><a href=\"/en-US/docs/Glossary/IRC\">IRC</a></li><li><a href=\"/en-US/docs/Glossary/ISO\">ISO</a></li><li><a href=\"/en-US/docs/Glossary/ISP\">ISP</a></li><li><a href=\"/en-US/docs/Glossary/ITU\">ITU</a></li><li><a href=\"/en-US/docs/Glossary/Jank\">Jank</a></li><li><a href=\"/en-US/docs/Glossary/Java\">Java</a></li><li><a href=\"/en-US/docs/Glossary/JavaScript\">JavaScript</a></li><li><a href=\"/en-US/docs/Glossary/Jitter\">Jitter</a></li><li><a href=\"/en-US/docs/Glossary/JPEG\">JPEG</a></li><li><a href=\"/en-US/docs/Glossary/JSON\">JSON</a></li><li><a href=\"/en-US/docs/Glossary/JSON_type_representation\">JSON type representation</a></li><li><a href=\"/en-US/docs/Glossary/Kebab_case\">Kebab case</a></li><li><a href=\"/en-US/docs/Glossary/Key\">Key</a></li><li><a href=\"/en-US/docs/Glossary/Keyword\">Keyword</a></li><li><a href=\"/en-US/docs/Glossary/Largest_contentful_paint\">Largest Contentful Paint (LCP)</a></li><li><a href=\"/en-US/docs/Glossary/Latency\">Latency</a></li><li><a href=\"/en-US/docs/Glossary/Layout_viewport\">Layout viewport</a></li><li><a href=\"/en-US/docs/Glossary/Lazy_load\">Lazy load</a></li><li><a href=\"/en-US/docs/Glossary/LGPL\">LGPL</a></li><li><a href=\"/en-US/docs/Glossary/Ligature\">Ligature</a></li><li><a href=\"/en-US/docs/Glossary/Literal\">Literal</a></li><li><a href=\"/en-US/docs/Glossary/Local_scope\">Local scope</a></li><li><a href=\"/en-US/docs/Glossary/Local_variable\">Local variable</a></li><li><a href=\"/en-US/docs/Glossary/Locale\">Locale</a></li><li><a href=\"/en-US/docs/Glossary/Localization\">Localization</a></li><li><a href=\"/en-US/docs/Glossary/Logical_properties\">Logical properties</a></li><li><a href=\"/en-US/docs/Glossary/Long_task\">Long task</a></li><li><a href=\"/en-US/docs/Glossary/Loop\">Loop</a></li><li><a href=\"/en-US/docs/Glossary/Lossless_compression\">Lossless compression</a></li><li><a href=\"/en-US/docs/Glossary/Lossy_compression\">Lossy compression</a></li><li><a href=\"/en-US/docs/Glossary/LTR\">LTR (Left To Right)</a></li><li><a href=\"/en-US/docs/Glossary/Main_Axis\">Main Axis</a></li><li><a href=\"/en-US/docs/Glossary/Main_thread\">Main thread</a></li><li><a href=\"/en-US/docs/Glossary/Markup\">Markup</a></li><li><a href=\"/en-US/docs/Glossary/MathML\">MathML</a></li><li><a href=\"/en-US/docs/Glossary/Media\">Media</a></li><li><a href=\"/en-US/docs/Glossary/Media_query\">Media query</a></li><li><a href=\"/en-US/docs/Glossary/Metadata\">Metadata</a></li><li><a href=\"/en-US/docs/Glossary/Method\">Method</a></li><li><a href=\"/en-US/docs/Glossary/Microsoft_Edge\">Microsoft Edge</a></li><li><a href=\"/en-US/docs/Glossary/Microsoft_Internet_Explorer\">Microsoft Internet Explorer</a></li><li><a href=\"/en-US/docs/Glossary/Middleware\">Middleware</a></li><li><a href=\"/en-US/docs/Glossary/MIME\">MIME</a></li><li><a href=\"/en-US/docs/Glossary/MIME_type\">MIME type</a></li><li><a href=\"/en-US/docs/Glossary/Minification\">Minification</a></li><li><a href=\"/en-US/docs/Glossary/MitM\">MitM</a></li><li><a href=\"/en-US/docs/Glossary/Mixin\">Mixin</a></li><li><a href=\"/en-US/docs/Glossary/Mobile_First\">Mobile First</a></li><li><a href=\"/en-US/docs/Glossary/Modem\">Modem</a></li><li><a href=\"/en-US/docs/Glossary/Modularity\">Modularity</a></li><li><a href=\"/en-US/docs/Glossary/Mozilla_Firefox\">Mozilla Firefox</a></li><li><a href=\"/en-US/docs/Glossary/Mutable\">Mutable</a></li><li><a href=\"/en-US/docs/Glossary/MVC\">MVC</a></li><li><a href=\"/en-US/docs/Glossary/Namespace\">Namespace</a></li><li><a href=\"/en-US/docs/Glossary/NaN\">NaN</a></li><li><a href=\"/en-US/docs/Glossary/NAT\">NAT</a></li><li><a href=\"/en-US/docs/Glossary/Native\">Native</a></li><li><a href=\"/en-US/docs/Glossary/Navigation_directive\">Navigation directive</a></li><li><a href=\"/en-US/docs/Glossary/Netscape_Navigator\">Netscape Navigator</a></li><li><a href=\"/en-US/docs/Glossary/Network_throttling\">Network throttling</a></li><li><a href=\"/en-US/docs/Glossary/NNTP\">NNTP</a></li><li><a href=\"/en-US/docs/Glossary/Node\">Node</a></li><li><a href=\"/en-US/docs/Glossary/Node.js\">Node.js</a></li><li><a href=\"/en-US/docs/Glossary/Non-normative\">Non-normative</a></li><li><a href=\"/en-US/docs/Glossary/Normative\">Normative</a></li><li><a href=\"/en-US/docs/Glossary/Null\">Null</a></li><li><a href=\"/en-US/docs/Glossary/Nullish\">Nullish value</a></li><li><a href=\"/en-US/docs/Glossary/Number\">Number</a></li><li><a href=\"/en-US/docs/Glossary/Object\">Object</a></li><li><a href=\"/en-US/docs/Glossary/Object_reference\">Object reference</a></li><li><a href=\"/en-US/docs/Glossary/OOP\">OOP</a></li><li><a href=\"/en-US/docs/Glossary/OpenGL\">OpenGL</a></li><li><a href=\"/en-US/docs/Glossary/OpenSSL\">OpenSSL</a></li><li><a href=\"/en-US/docs/Glossary/Opera_Browser\">Opera Browser</a></li><li><a href=\"/en-US/docs/Glossary/Operand\">Operand</a></li><li><a href=\"/en-US/docs/Glossary/Operator\">Operator</a></li><li><a href=\"/en-US/docs/Glossary/Origin\">Origin</a></li><li><a href=\"/en-US/docs/Glossary/OTA\">OTA</a></li><li><a href=\"/en-US/docs/Glossary/OWASP\">OWASP</a></li><li><a href=\"/en-US/docs/Glossary/P2P\">P2P</a></li><li><a href=\"/en-US/docs/Glossary/PAC\">PAC</a></li><li><a href=\"/en-US/docs/Glossary/Packet\">Packet</a></li><li><a href=\"/en-US/docs/Glossary/Page_load_time\">Page load time</a></li><li><a href=\"/en-US/docs/Glossary/Page_prediction\">Page prediction</a></li><li><a href=\"/en-US/docs/Glossary/Parameter\">Parameter</a></li><li><a href=\"/en-US/docs/Glossary/Parent_object\">Parent object</a></li><li><a href=\"/en-US/docs/Glossary/Parse\">Parse</a></li><li><a href=\"/en-US/docs/Glossary/Parser\">Parser</a></li><li><a href=\"/en-US/docs/Glossary/Payload_body\">Payload body</a></li><li><a href=\"/en-US/docs/Glossary/Payload_header\">Payload header</a></li><li><a href=\"/en-US/docs/Glossary/PDF\">PDF</a></li><li><a href=\"/en-US/docs/Glossary/Perceived_performance\">Perceived performance</a></li><li><a href=\"/en-US/docs/Glossary/Percent-encoding\">Percent-encoding</a></li><li><a href=\"/en-US/docs/Glossary/PHP\">PHP</a></li><li><a href=\"/en-US/docs/Glossary/Physical_properties\">Physical properties</a></li><li><a href=\"/en-US/docs/Glossary/Pixel\">Pixel</a></li><li><a href=\"/en-US/docs/Glossary/Placeholder_names\">Placeholder names</a></li><li><a href=\"/en-US/docs/Glossary/Plaintext\">Plaintext</a></li><li><a href=\"/en-US/docs/Glossary/Plugin\">Plugin</a></li><li><a href=\"/en-US/docs/Glossary/PNG\">PNG</a></li><li><a href=\"/en-US/docs/Glossary/Polyfill\">Polyfill</a></li><li><a href=\"/en-US/docs/Glossary/Polymorphism\">Polymorphism</a></li><li><a href=\"/en-US/docs/Glossary/POP\">POP3</a></li><li><a href=\"/en-US/docs/Glossary/Port\">Port</a></li><li><a href=\"/en-US/docs/Glossary/Prefetch\">Prefetch</a></li><li><a href=\"/en-US/docs/Glossary/Preflight_request\">Preflight request</a></li><li><a href=\"/en-US/docs/Glossary/Prerender\">Prerender</a></li><li><a href=\"/en-US/docs/Glossary/Presto\">Presto</a></li><li><a href=\"/en-US/docs/Glossary/Primitive\">Primitive</a></li><li><a href=\"/en-US/docs/Glossary/Privileged\">Privileged</a></li><li><a href=\"/en-US/docs/Glossary/Privileged_code\">Privileged code</a></li><li><a href=\"/en-US/docs/Glossary/Progressive_Enhancement\">Progressive Enhancement</a></li><li><a href=\"/en-US/docs/Glossary/Progressive_web_apps\">Progressive web apps</a></li><li><a href=\"/en-US/docs/Glossary/Promise\">Promise</a></li><li><a href=\"/en-US/docs/Glossary/Property\">Property</a></li><li><a href=\"/en-US/docs/Glossary/Protocol\">Protocol</a></li><li><a href=\"/en-US/docs/Glossary/Prototype\">Prototype</a></li><li><a href=\"/en-US/docs/Glossary/Prototype-based_programming\">Prototype-based programming</a></li><li><a href=\"/en-US/docs/Glossary/Proxy_server\">Proxy server</a></li><li><a href=\"/en-US/docs/Glossary/Pseudo-class\">Pseudo-class</a></li><li><a href=\"/en-US/docs/Glossary/Pseudo-element\">Pseudo-element</a></li><li><a href=\"/en-US/docs/Glossary/Pseudocode\">Pseudocode</a></li><li><a href=\"/en-US/docs/Glossary/Public-key_cryptography\">Public-key cryptography</a></li><li><a href=\"/en-US/docs/Glossary/Python\">Python</a></li><li><a href=\"/en-US/docs/Glossary/Quality_values\">Quality values</a></li><li><a href=\"/en-US/docs/Glossary/Quaternion\">Quaternion</a></li><li><a href=\"/en-US/docs/Glossary/QUIC\">QUIC</a></li><li><a href=\"/en-US/docs/Glossary/RAIL\">RAIL</a></li><li><a href=\"/en-US/docs/Glossary/RNG\">Random Number Generator</a></li><li><a href=\"/en-US/docs/Glossary/Raster_image\">Raster image</a></li><li><a href=\"/en-US/docs/Glossary/Rate_limit\">Rate limit</a></li><li><a href=\"/en-US/docs/Glossary/RDF\">RDF</a></li><li><a href=\"/en-US/docs/Glossary/Real_User_Monitoring\">Real User Monitoring (RUM)</a></li><li><a href=\"/en-US/docs/Glossary/Recursion\">Recursion</a></li><li><a href=\"/en-US/docs/Glossary/Reflow\">Reflow</a></li><li><a href=\"/en-US/docs/Glossary/Regular_expression\">Regular expression</a></li><li><a href=\"/en-US/docs/Glossary/Relying_party\">Relying party</a></li><li><a href=\"/en-US/docs/Glossary/Render_blocking\">Render-blocking</a></li><li><a href=\"/en-US/docs/Glossary/Repaint\">Repaint</a></li><li><a href=\"/en-US/docs/Glossary/Replay_attack\">Replay attack</a></li><li><a href=\"/en-US/docs/Glossary/Repo\">Repo</a></li><li><a href=\"/en-US/docs/Glossary/Reporting_directive\">Reporting directive</a></li><li><a href=\"/en-US/docs/Glossary/Representation_header\">Representation header</a></li><li><a href=\"/en-US/docs/Glossary/Request_header\">Request header</a></li><li><a href=\"/en-US/docs/Glossary/Resource_Timing\">Resource Timing</a></li><li><a href=\"/en-US/docs/Glossary/Response_header\">Response header</a></li><li><a href=\"/en-US/docs/Glossary/Responsive_web_design\">Responsive web design</a></li><li><a href=\"/en-US/docs/Glossary/REST\">REST</a></li><li><a href=\"/en-US/docs/Glossary/RGB\">RGB</a></li><li><a href=\"/en-US/docs/Glossary/RIL\">RIL</a></li><li><a href=\"/en-US/docs/Glossary/Robots.txt\">Robots.txt</a></li><li><a href=\"/en-US/docs/Glossary/Round_Trip_Time\">Round Trip Time (RTT)</a></li><li><a href=\"/en-US/docs/Glossary/Router\">Router</a></li><li><a href=\"/en-US/docs/Glossary/RSS\">RSS</a></li><li><a href=\"/en-US/docs/Glossary/Rsync\">Rsync</a></li><li><a href=\"/en-US/docs/Glossary/RTCP\">RTCP (RTP Control Protocol)</a></li><li><a href=\"/en-US/docs/Glossary/RTF\">RTF</a></li><li><a href=\"/en-US/docs/Glossary/RTL\">RTL (Right to Left)</a></li><li><a href=\"/en-US/docs/Glossary/RTP\">RTP (Real-time Transport Protocol) and SRTP (Secure RTP)</a></li><li><a href=\"/en-US/docs/Glossary/RTSP\">RTSP: Real-time streaming protocol</a></li><li><a href=\"/en-US/docs/Glossary/Ruby\">Ruby</a></li><li><a href=\"/en-US/docs/Glossary/Safe\">Safe</a></li><li><a href=\"/en-US/docs/Glossary/Salt\">Salt</a></li><li><a href=\"/en-US/docs/Glossary/Same-origin_policy\">Same-origin policy</a></li><li><a href=\"/en-US/docs/Glossary/SCM\">SCM</a></li><li><a href=\"/en-US/docs/Glossary/Scope\">Scope</a></li><li><a href=\"/en-US/docs/Glossary/Screen_reader\">Screen reader</a></li><li><a href=\"/en-US/docs/Glossary/Script-supporting_element\">Script-supporting element</a></li><li><a href=\"/en-US/docs/Glossary/Scroll_boundary\">Scroll boundary</a></li><li><a href=\"/en-US/docs/Glossary/Scroll_chaining\">Scroll chaining</a></li><li><a href=\"/en-US/docs/Glossary/Scroll_container\">Scroll container</a></li><li><a href=\"/en-US/docs/Glossary/Scroll_snap\">Scroll snap</a></li><li><a href=\"/en-US/docs/Glossary/SCTP\">SCTP</a></li><li><a href=\"/en-US/docs/Glossary/SDK\">SDK (Software Development Kit)</a></li><li><a href=\"/en-US/docs/Glossary/SDP\">SDP</a></li><li><a href=\"/en-US/docs/Glossary/Search_engine\">Search engine</a></li><li><a href=\"/en-US/docs/Glossary/Secure_Context\">Secure Context</a></li><li><a href=\"/en-US/docs/Glossary/SSL\">Secure Sockets Layer (SSL)</a></li><li><a href=\"/en-US/docs/Glossary/CSS_Selector\">Selector (CSS)</a></li><li><a href=\"/en-US/docs/Glossary/Self-Executing_Anonymous_Function\">Self-Executing Anonymous Function</a></li><li><a href=\"/en-US/docs/Glossary/Semantics\">Semantics</a></li><li><a href=\"/en-US/docs/Glossary/SEO\">SEO</a></li><li><a href=\"/en-US/docs/Glossary/Serializable_object\">Serializable object</a></li><li><a href=\"/en-US/docs/Glossary/Serialization\">Serialization</a></li><li><a href=\"/en-US/docs/Glossary/Server\">Server</a></li><li><a href=\"/en-US/docs/Glossary/Server_Timing\">Server Timing</a></li><li><a href=\"/en-US/docs/Glossary/Session_Hijacking\">Session Hijacking</a></li><li><a href=\"/en-US/docs/Glossary/SGML\">SGML</a></li><li><a href=\"/en-US/docs/Glossary/Shadow_tree\">Shadow tree</a></li><li><a href=\"/en-US/docs/Glossary/Shallow_copy\">Shallow copy</a></li><li><a href=\"/en-US/docs/Glossary/Shim\">Shim</a></li><li><a href=\"/en-US/docs/Glossary/Signature\">Signature</a></li><li><a href=\"/en-US/docs/Glossary/SIMD\">SIMD</a></li><li><a href=\"/en-US/docs/Glossary/SISD\">SISD</a></li><li><a href=\"/en-US/docs/Glossary/Site\">Site</a></li><li><a href=\"/en-US/docs/Glossary/Site_map\">Site map</a></li><li><a href=\"/en-US/docs/Glossary/SLD\">SLD</a></li><li><a href=\"/en-US/docs/Glossary/Sloppy_mode\">Sloppy mode</a></li><li><a href=\"/en-US/docs/Glossary/Slug\">Slug</a></li><li><a href=\"/en-US/docs/Glossary/Smoke_Test\">Smoke Test</a></li><li><a href=\"/en-US/docs/Glossary/SMPTE\">SMPTE (Society of Motion Picture and Television Engineers)</a></li><li><a href=\"/en-US/docs/Glossary/SMTP\">SMTP</a></li><li><a href=\"/en-US/docs/Glossary/Snake_case\">Snake case</a></li><li><a href=\"/en-US/docs/Glossary/Snap_positions\">Snap positions</a></li><li><a href=\"/en-US/docs/Glossary/SOAP\">SOAP</a></li><li><a href=\"/en-US/docs/Glossary/SPA\">SPA (Single-page application)</a></li><li><a href=\"/en-US/docs/Glossary/Specification\">Specification</a></li><li><a href=\"/en-US/docs/Glossary/Speculative_parsing\">Speculative parsing</a></li><li><a href=\"/en-US/docs/Glossary/Speed_index\">Speed index</a></li><li><a href=\"/en-US/docs/Glossary/SQL\">SQL</a></li><li><a href=\"/en-US/docs/Glossary/SQL_Injection\">SQL Injection</a></li><li><a href=\"/en-US/docs/Glossary/SRI\">SRI</a></li><li><a href=\"/en-US/docs/Glossary/Stacking_context\">Stacking context</a></li><li><a href=\"/en-US/docs/Glossary/State_machine\">State machine</a></li><li><a href=\"/en-US/docs/Glossary/Statement\">Statement</a></li><li><a href=\"/en-US/docs/Glossary/Static_method\">Static method</a></li><li><a href=\"/en-US/docs/Glossary/SSG\">Static site generator (SSG)</a></li><li><a href=\"/en-US/docs/Glossary/Static_typing\">Static typing</a></li><li><a href=\"/en-US/docs/Glossary/Sticky_activation\">Sticky activation</a></li><li><a href=\"/en-US/docs/Glossary/Strict_mode\">Strict mode</a></li><li><a href=\"/en-US/docs/Glossary/String\">String</a></li><li><a href=\"/en-US/docs/Glossary/Stringifier\">Stringifier</a></li><li><a href=\"/en-US/docs/Glossary/STUN\">STUN</a></li><li><a href=\"/en-US/docs/Glossary/Style_origin\">Style origin</a></li><li><a href=\"/en-US/docs/Glossary/Stylesheet\">Stylesheet</a></li><li><a href=\"/en-US/docs/Glossary/Submit_button\">Submit button</a></li><li><a href=\"/en-US/docs/Glossary/SVG\">SVG</a></li><li><a href=\"/en-US/docs/Glossary/SVN\">SVN</a></li><li><a href=\"/en-US/docs/Glossary/Symbol\">Symbol</a></li><li><a href=\"/en-US/docs/Glossary/Symmetric-key_cryptography\">Symmetric-key cryptography</a></li><li><a href=\"/en-US/docs/Glossary/Synchronous\">Synchronous</a></li><li><a href=\"/en-US/docs/Glossary/Syntax\">Syntax</a></li><li><a href=\"/en-US/docs/Glossary/Syntax_error\">Syntax error</a></li><li><a href=\"/en-US/docs/Glossary/Synthetic_monitoring\">Synthetic monitoring</a></li><li><a href=\"/en-US/docs/Glossary/Table_Grid_Box\">Table grid box</a></li><li><a href=\"/en-US/docs/Glossary/Table_Wrapper_Box\">Table Wrapper Box</a></li><li><a href=\"/en-US/docs/Glossary/Tag\">Tag</a></li><li><a href=\"/en-US/docs/Glossary/TCP\">TCP</a></li><li><a href=\"/en-US/docs/Glossary/TCP_handshake\">TCP handshake</a></li><li><a href=\"/en-US/docs/Glossary/TCP_slow_start\">TCP slow start</a></li><li><a href=\"/en-US/docs/Glossary/Telnet\">Telnet</a></li><li><a href=\"/en-US/docs/Glossary/Texel\">Texel</a></li><li><a href=\"/en-US/docs/Glossary/Khronos\">The Khronos Group</a></li><li><a href=\"/en-US/docs/Glossary/Thread\">Thread</a></li><li><a href=\"/en-US/docs/Glossary/Three_js\">Three js</a></li><li><a href=\"/en-US/docs/Glossary/Throttle\">Throttle</a></li><li><a href=\"/en-US/docs/Glossary/Time_to_first_byte\">Time to first byte</a></li><li><a href=\"/en-US/docs/Glossary/Time_to_interactive\">Time to interactive</a></li><li><a href=\"/en-US/docs/Glossary/TLD\">TLD</a></li><li><a href=\"/en-US/docs/Glossary/TOFU\">TOFU</a></li><li><a href=\"/en-US/docs/Glossary/Top_layer\">Top layer</a></li><li><a href=\"/en-US/docs/Glossary/Transient_activation\">Transient activation</a></li><li><a href=\"/en-US/docs/Glossary/TLS\">Transport Layer Security (TLS)</a></li><li><a href=\"/en-US/docs/Glossary/Tree_shaking\">Tree shaking</a></li><li><a href=\"/en-US/docs/Glossary/Trident\">Trident</a></li><li><a href=\"/en-US/docs/Glossary/Truthy\">Truthy</a></li><li><a href=\"/en-US/docs/Glossary/TTL\">TTL</a></li><li><a href=\"/en-US/docs/Glossary/TURN\">TURN</a></li><li><a href=\"/en-US/docs/Glossary/Type\">Type</a></li><li><a href=\"/en-US/docs/Glossary/Type_coercion\">Type coercion</a></li><li><a href=\"/en-US/docs/Glossary/Type_Conversion\">Type conversion</a></li><li><a href=\"/en-US/docs/Glossary/TypeScript\">TypeScript</a></li><li><a href=\"/en-US/docs/Glossary/UAAG\">UAAG</a></li><li><a href=\"/en-US/docs/Glossary/UDP\">UDP (User Datagram Protocol)</a></li><li><a href=\"/en-US/docs/Glossary/UI\">UI</a></li><li><a href=\"/en-US/docs/Glossary/Undefined\">Undefined</a></li><li><a href=\"/en-US/docs/Glossary/Unicode\">Unicode</a></li><li><a href=\"/en-US/docs/Glossary/Unix_time\">Unix time</a></li><li><a href=\"/en-US/docs/Glossary/URI\">URI</a></li><li><a href=\"/en-US/docs/Glossary/URL\">URL</a></li><li><a href=\"/en-US/docs/Glossary/URN\">URN</a></li><li><a href=\"/en-US/docs/Glossary/Usenet\">Usenet</a></li><li><a href=\"/en-US/docs/Glossary/User_agent\">User agent</a></li><li><a href=\"/en-US/docs/Glossary/UTF-8\">UTF-8</a></li><li><a href=\"/en-US/docs/Glossary/UUID\">UUID</a></li><li><a href=\"/en-US/docs/Glossary/UX\">UX</a></li><li><a href=\"/en-US/docs/Glossary/Validator\">Validator</a></li><li><a href=\"/en-US/docs/Glossary/Value\">Value</a></li><li><a href=\"/en-US/docs/Glossary/Variable\">Variable</a></li><li><a href=\"/en-US/docs/Glossary/Vendor_Prefix\">Vendor Prefix</a></li><li><a href=\"/en-US/docs/Glossary/Viewport\">Viewport</a></li><li><a href=\"/en-US/docs/Glossary/Visual_Viewport\">Visual Viewport</a></li><li><a href=\"/en-US/docs/Glossary/Void_element\">Void element</a></li><li><a href=\"/en-US/docs/Glossary/VoIP\">VoIP</a></li><li><a href=\"/en-US/docs/Glossary/W3C\">W3C</a></li><li><a href=\"/en-US/docs/Glossary/WAI\">WAI</a></li><li><a href=\"/en-US/docs/Glossary/WCAG\">WCAG</a></li><li><a href=\"/en-US/docs/Glossary/Web_performance\">Web performance</a></li><li><a href=\"/en-US/docs/Glossary/Web_server\">Web server</a></li><li><a href=\"/en-US/docs/Glossary/Web_standards\">Web standards</a></li><li><a href=\"/en-US/docs/Glossary/WebAssembly\">WebAssembly</a></li><li><a href=\"/en-US/docs/Glossary/WebDAV\">WebDAV</a></li><li><a href=\"/en-US/docs/Glossary/WebExtensions\">WebExtensions</a></li><li><a href=\"/en-US/docs/Glossary/WebGL\">WebGL</a></li><li><a href=\"/en-US/docs/Glossary/WebIDL\">WebIDL</a></li><li><a href=\"/en-US/docs/Glossary/WebKit\">WebKit</a></li><li><a href=\"/en-US/docs/Glossary/WebM\">WebM</a></li><li><a href=\"/en-US/docs/Glossary/WebP\">WebP</a></li><li><a href=\"/en-US/docs/Glossary/WebRTC\">WebRTC</a></li><li><a href=\"/en-US/docs/Glossary/WebSockets\">WebSockets</a></li><li><a href=\"/en-US/docs/Glossary/WebVTT\">WebVTT</a></li><li><a href=\"/en-US/docs/Glossary/WHATWG\">WHATWG</a></li><li><a href=\"/en-US/docs/Glossary/Whitespace\">Whitespace</a></li><li><a href=\"/en-US/docs/Glossary/WindowProxy\">WindowProxy</a></li><li><a href=\"/en-US/docs/Glossary/World_Wide_Web\">World Wide Web</a></li><li><a href=\"/en-US/docs/Glossary/Wrapper\">Wrapper</a></li><li><a href=\"/en-US/docs/Glossary/XForms\">XForms</a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Glossary/XHTML\">XHTML</a></li><li><a href=\"/en-US/docs/Glossary/XInclude\">XInclude</a></li><li><a href=\"/en-US/docs/Glossary/XLink\">XLink</a></li><li><a href=\"/en-US/docs/Glossary/XML\">XML</a></li><li><a href=\"/en-US/docs/Glossary/XMLHttpRequest\">XMLHttpRequest (XHR)</a></li><li><a href=\"/en-US/docs/Glossary/XPath\">XPath</a></li><li><a href=\"/en-US/docs/Glossary/XQuery\">XQuery</a></li><li><a href=\"/en-US/docs/Glossary/XSLT\">XSLT</a></li><li><a href=\"/en-US/docs/Glossary/Zstandard_compression\">Zstandard compression</a></li></ol>\n </li>\n </ol>\n","sidebarMacro":"GlossarySidebar","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>A <strong>cacheable</strong> response is an HTTP response that can be cached, that is stored to be retrieved and used later, saving a new request to the server. Not all HTTP responses can be cached; these are the constraints for an HTTP response to be cacheable:</p>\n<ul>\n <li>The method used in the request is <em>cacheable</em>, that is either a <a href=\"/en-US/docs/Web/HTTP/Methods/GET\"><code>GET</code></a> or a <a href=\"/en-US/docs/Web/HTTP/Methods/HEAD\"><code>HEAD</code></a> method. A response to a <a href=\"/en-US/docs/Web/HTTP/Methods/POST\"><code>POST</code></a> or <a href=\"/en-US/docs/Web/HTTP/Methods/PATCH\"><code>PATCH</code></a> request can also be cached if freshness is indicated and the <a href=\"/en-US/docs/Web/HTTP/Headers/Content-Location\"><code>Content-Location</code></a> header is set, but this is rarely implemented. For example, Firefox does not support it (<a href=\"https://bugzil.la/109553\" class=\"external\" target=\"_blank\">Firefox bug 109553</a>). Other methods, like <a href=\"/en-US/docs/Web/HTTP/Methods/PUT\"><code>PUT</code></a> or <a href=\"/en-US/docs/Web/HTTP/Methods/DELETE\"><code>DELETE</code></a> are not cacheable and their result cannot be cached.</li>\n <li>The status code of the response is <em>known</em> by the application caching, and is <em>cacheable</em>. The following status codes are cacheable: <a href=\"/en-US/docs/Web/HTTP/Status/200\"><code>200</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/203\"><code>203</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/204\"><code>204</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/206\"><code>206</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/300\"><code>300</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/301\"><code>301</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/404\"><code>404</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/405\"><code>405</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/410\"><code>410</code></a>, <a href=\"/en-US/docs/Web/HTTP/Status/414\"><code>414</code></a>, and <a href=\"/en-US/docs/Web/HTTP/Status/501\"><code>501</code></a>.</li>\n <li>There are no specific headers in the response, like <a href=\"/en-US/docs/Web/HTTP/Headers/Cache-Control\"><code>Cache-Control</code></a>, with values that would prohibit caching.</li>\n</ul>\n<p>Note that some requests with non-cacheable responses to a specific URI may invalidate previously cached responses from the same URI. For example, a <a href=\"/en-US/docs/Web/HTTP/Methods/PUT\"><code>PUT</code></a> to <code>/pageX.html</code> will invalidate all cached responses to <a href=\"/en-US/docs/Web/HTTP/Methods/GET\"><code>GET</code></a> or <a href=\"/en-US/docs/Web/HTTP/Methods/HEAD\"><code>HEAD</code></a> requests to <code>/pageX.html</code>.</p>\n<p>When both the method of the request and the status of the response are cacheable, the response to the request can be cached:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">http</span></div><pre class=\"brush: http notranslate\"><code>GET /pageX.html HTTP/1.1\n(…)\n\n200 OK\n(…)\n</code></pre></div>\n<p>The response to a <a href=\"/en-US/docs/Web/HTTP/Methods/PUT\"><code>PUT</code></a> request cannot be cached. Moreover, it invalidates cached data for requests to the same URI using <a href=\"/en-US/docs/Web/HTTP/Methods/HEAD\"><code>HEAD</code></a> or <a href=\"/en-US/docs/Web/HTTP/Methods/GET\"><code>GET</code></a> methods:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">http</span></div><pre class=\"brush: http notranslate\"><code>PUT /pageX.html HTTP/1.1\n(…)\n\n200 OK\n(…)\n</code></pre></div>\n<p>The presence of the <a href=\"/en-US/docs/Web/HTTP/Headers/Cache-Control\"><code>Cache-Control</code></a> header with a particular value in the response can prevent caching:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">http</span></div><pre class=\"brush: http notranslate\"><code>GET /pageX.html HTTP/1.1\n(…)\n\n200 OK\nCache-Control: no-cache\n(…)\n</code></pre></div>"}},{"type":"prose","value":{"id":"see_also","title":"See also","isH3":false,"content":"<ul>\n <li>Details about <a href=\"https://httpwg.org/specs/rfc9110.html#rfc.section.9.2.3\" class=\"external\" target=\"_blank\">methods and caching</a> are provided in the HTTP specification.</li>\n <li>Description of common cacheable methods: <a href=\"/en-US/docs/Web/HTTP/Methods/GET\"><code>GET</code></a>, <a href=\"/en-US/docs/Web/HTTP/Methods/HEAD\"><code>HEAD</code></a></li>\n <li>Description of common non-cacheable methods: <a href=\"/en-US/docs/Web/HTTP/Methods/PUT\"><code>PUT</code></a>, <a href=\"/en-US/docs/Web/HTTP/Methods/DELETE\"><code>DELETE</code></a>, often <a href=\"/en-US/docs/Web/HTTP/Methods/POST\"><code>POST</code></a></li>\n</ul>"}}],"toc":[{"text":"See also","id":"see_also"}],"summary":"A cacheable response is an HTTP response that can be cached, that is stored to be retrieved and used later, saving a new request to the server. Not all HTTP responses can be cached; these are the constraints for an HTTP response to be cacheable:","popularity":0,"modified":"2024-01-22T14:47:59.000Z","other_translations":[{"locale":"de","title":"Cacheable","native":"Deutsch"},{"locale":"es","title":"Cacheable","native":"Español"},{"locale":"fr","title":"Apte à être mis en cache","native":"Français"},{"locale":"ja","title":"Cacheable (キャッシュ可能)","native":"日本語"},{"locale":"ko","title":"Cacheable","native":"한국어"},{"locale":"ru","title":"Кешируемые методы","native":"Русский"},{"locale":"zh-CN","title":"可缓存","native":"中文 (简体)"},{"locale":"zh-TW","title":"可緩存","native":"正體中文 (繁體)"}],"pageType":"glossary-definition","source":{"folder":"en-us/glossary/cacheable","github_url":"https://github.com/mdn/content/blob/main/files/en-us/glossary/cacheable/index.md","last_commit_url":"https://github.com/mdn/content/commit/35d631c3a3f4050344ffb8c1bf033137943c10b6","filename":"index.md"},"short_title":"Cacheable","parents":[{"uri":"/en-US/docs/Glossary","title":"Glossary"},{"uri":"/en-US/docs/Glossary/Cacheable","title":"Cacheable"}],"pageTitle":"Cacheable - MDN Web Docs Glossary: Definitions of Web-related terms | MDN","noIndexing":false}}</script></body></html>