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WebAssembly
<!doctype html> <html lang="en"> <head> <meta charset="utf-8" /> <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes" /> <meta property="og:title" content="WebAssembly" /> <meta property="og:description" content="WebAssembly (abbreviated Wasm) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable compilation target for programming languages, enabling deployment on the web for client and server applications." /> <meta property="og:type" content="website" /> <meta property="og:url" content="https://webassembly.org/" /> <meta property="og:image" content="https://v1.screenshot.11ty.dev/https%3A%2F%2Fwebassembly.org%2F/opengraph/" /> <title>WebAssembly</title> <link rel="stylesheet" type="text/css" href="/css/custom.css" /> <noscript id="dark-mode-toggle-stylesheets"> <link rel="stylesheet" type="text/css" href="/css/light.css" media="(prefers-color-scheme: light)" /> <link rel="stylesheet" type="text/css" href="/css/dark.css" media="(prefers-color-scheme: dark)" /> <meta name="color-scheme" content="dark light" /> </noscript> <script src="/js/dark-mode-toggle-stylesheets-loader.min.js"></script> <script type="module" src="/js/dark-mode-toggle.min.mjs"></script> <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" /> <link rel="icon" href="/favicon.ico" type="image/x-icon" /> <link rel="alternate" type="application/atom+xml" title="WebAssembly News" href="/feed.xml"> </head> <body> <header class="page-section"> <div class="container-narrow"> <a class="site-logo" href="/" title="WebAssembly"></a> <nav class="site-nav"> <a class="site-nav-item btn" href="/">Overview</a> <a class="site-nav-item btn" href="/getting-started/developers-guide/" >Getting Started</a > <a class="site-nav-item btn" href="/specs">Specs</a> <a class="site-nav-item btn" href="/docs/faq/">Docs</a> <a class="site-nav-item btn" href="/features/">Feature Extensions</a> <a class="site-nav-item btn" href="/community/resources/" >Community</a > <a class="site-nav-item btn" href="/news/" >News</a > </nav> </div> </header> <section class="page-section-spacious flush-bottom"> <div class="container-narrow"> <p class="lead">WebAssembly (abbreviated <i>Wasm</i>) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable compilation target for programming languages, enabling deployment on the web for client and server applications.</p> </div> </section> <section> <div class="container"><div class="flash flash-warn"> Developer reference documentation for Wasm can be found on <a href="https://developer.mozilla.org/en-US/docs/WebAssembly">MDN's WebAssembly pages</a>. The open standards for WebAssembly are developed in a <a href="https://www.w3.org/community/webassembly/">W3C Community Group</a> (that includes representatives from all major browsers) as well as a <a href="https://www.w3.org/wasm/">W3C Working Group</a>. </div> <div class="row"> <div class="bubble col-xs-12 col-md-6"> <h3>Efficient and fast</h3> <p>The Wasm <a href="https://webassembly.github.io/spec/core/exec/index.html">stack machine</a> is designed to be encoded in a size- and load-time-efficient <a href="https://webassembly.github.io/spec/core/binary/index.html">binary format</a>. WebAssembly aims to execute at native speed by taking advantage of <a href="/docs/portability/#assumptions-for-efficient-execution">common hardware capabilities</a> available on a wide range of platforms.</p> </div> <div class="bubble col-xs-12 col-md-6"> <h3>Safe</h3> <p>WebAssembly describes a memory-safe, sandboxed <a href="https://webassembly.github.io/spec/core/exec/index.html#linear-memory">execution environment</a> that may even be implemented inside existing JavaScript virtual machines. When <a href="/docs/web/">embedded in the web</a>, WebAssembly will enforce the same-origin and permissions security policies of the browser.</p> </div> </div> <div class="row"> <div class="bubble col-xs-12 col-md-6"> <h3>Open and debuggable</h3> <p>WebAssembly is designed to be pretty-printed in a <a href="https://webassembly.github.io/spec/core/text/index.html">textual format</a> for debugging, testing, experimenting, optimizing, learning, teaching, and writing programs by hand. The textual format will be used when <a href="/docs/faq/#will-webassembly-support-view-source-on-the-web">viewing the source</a> of Wasm modules on the web.</p> </div> <div class="bubble col-xs-12 col-md-6"> <h3>Part of the open web platform</h3> <p>WebAssembly is designed to maintain the versionless, feature-tested, and backwards-compatible <a href="/docs/web/">nature of the web</a>. WebAssembly modules will be able to call into and out of the JavaScript context and access browser functionality through the same Web APIs accessible from JavaScript. WebAssembly also supports <a href="/docs/non-web/">non-web</a> embeddings.</p> </div> </div> </div> </section> <footer class="container"> <dark-mode-toggle dark="Light Mode" light="Dark Mode" permanent></dark-mode-toggle> </footer> </body> </html>