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Introduction | Postmark Developer Documentation
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</header> <div class="page"> <div class="container"> <section id="toc" class="docs-toc docs-toc--desktop"> <h3>Overview</h3> <ul> <li class="active"> <a href="/developer">Introduction</a> </li> </ul> <h3>Integration</h3> <ul> <li class=""> <a href="https://postmarkapp.com/developer/integration/official-libraries"> Official libraries </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/integration/community-libraries"> Community libraries </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/integration/other-tools-and-integrations"> Tools and Integrations </a> </li> </ul> <h3>User guide</h3> <ul> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/send-email-with-api"> Sending email with API </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/send-email-with-smtp"> Sending email with SMTP </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/inbound"> Processing email </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/tracking-opens"> Tracking opens </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/tracking-links"> Tracking links </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/managing-your-account"> Managing your account </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/user-guide/sandbox-mode"> Sandbox mode </a> </li> </ul> <h3>API reference</h3> <ul> <li class=""> <a href="https://postmarkapp.com/developer/api/overview"> Overview </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/email-api"> Email </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/bulk-email"> Bulk </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/bounce-api"> Bounce </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/templates-api"> Templates </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/server-api"> Server </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/servers-api"> Servers </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/message-streams-api"> Message Streams </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/messages-api"> Messages </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/domains-api"> Domains </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/signatures-api"> Sender signatures </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/stats-api"> Stats </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/inbound-rules-triggers-api"> Triggers: Inbound rules </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/webhooks-api"> Webhooks </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/suppressions-api"> Suppressions </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/api/data-removals-api"> Data Removal </a> </li> </ul> <h3>Webhooks</h3> <ul> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/webhooks-overview"> Webhooks overview </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/bounce-webhook"> Bounce webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/inbound-webhook"> Inbound webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/open-tracking-webhook"> Open tracking webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/delivery-webhook"> Delivery webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/click-webhook"> Click webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook"> Spam complaint webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/subscription-change-webhook"> Subscription change webhook </a> </li> <li class=""> <a href="https://postmarkapp.com/developer/webhooks/smtp-api-error"> SMTP API Error </a> </li> </ul> </section> <div class="docs-toc docs-toc--mobile"> <select> <optgroup label="Overview"> <option value="/developer">Introduction</option> </optgroup> <optgroup label="Integration"> <option value="https://postmarkapp.com/developer/integration/official-libraries" >Official libraries</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#rails-gem" >- Rails gem</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#ruby-gem" >- Ruby gem</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#dot-net" >- .NET</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#java" >- Java</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#php" >- PHP</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#postmark-craft-plugin" >- Craft plugin</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#node-js" >- Node.js</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#postmark-cli" >- CLI</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#wordpress" >- WordPress plugin</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#grunt" >- Grunt plugin</option> <option value="https://postmarkapp.com/developer/integration/official-libraries#postmark-zapier-actions" >- Zapier Actions</option> <option value="https://postmarkapp.com/developer/integration/community-libraries" >Community libraries</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#classic-asp" >- Classic ASP</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#clojure" >- Clojure</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#coldfusion" >- ColdFusion</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#django" >- Django</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#drupal-module" >- Drupal module</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#elixir" >- Elixir</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#erlang" >- Erlang</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#google-go" >- Google Go</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#grails-plugin" >- Grails plugin</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#haskell" >- Haskell</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#java" >- Java</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#laravel" >- Laravel</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#magento-extension" >- Magento extension</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#node-js" >- Node.js</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#objective-c" >- Objective-C</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#perl-wwwpostmark" >- Perl</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#pharo-smalltalk" >- Pharo Smalltalk</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#php-5" >- PHP 5</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#powershell-snap-in" >- PowerShell Snap-in</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#python" >- Python</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#scala" >- Scala</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#swift" >- Swift</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#wordpress-plugins" >- WordPress</option> <option value="https://postmarkapp.com/developer/integration/community-libraries#zend" >- Zend</option> <option value="https://postmarkapp.com/developer/integration/other-tools-and-integrations" >Tools and Integrations</option> </optgroup> <optgroup label="User guide"> <option value="https://postmarkapp.com/developer/user-guide/send-email-with-api" >Sending email with API</option> <option value="https://postmarkapp.com/developer/user-guide/send-email-with-api/send-a-single-email" >- Send a single email</option> <option value="https://postmarkapp.com/developer/user-guide/send-email-with-api/batch-emails" >- Send batch emails</option> <option value="https://postmarkapp.com/developer/user-guide/send-email-with-smtp" >Sending email with SMTP</option> <option value="https://postmarkapp.com/developer/user-guide/inbound" >Processing email</option> <option value="https://postmarkapp.com/developer/user-guide/inbound/configure-an-inbound-server" >- Configure an inbound server</option> <option value="https://postmarkapp.com/developer/user-guide/inbound/inbound-domain-forwarding" >- Inbound domain forwarding</option> <option value="https://postmarkapp.com/developer/user-guide/inbound/parse-an-email" >- Parse an email</option> <option value="https://postmarkapp.com/developer/user-guide/inbound/configure-inbound-blocking" >- Configure inbound blocking</option> <option value="https://postmarkapp.com/developer/user-guide/inbound/sample-inbound-workflow" >- Sample inbound workflow</option> <option value="https://postmarkapp.com/developer/user-guide/tracking-opens" >Tracking opens</option> <option value="https://postmarkapp.com/developer/user-guide/tracking-opens/tracking-opens-per-message-stream" >- Tracking opens per Server</option> <option value="https://postmarkapp.com/developer/user-guide/tracking-opens/tracking-opens-per-email" >- Tracking opens per email</option> <option value="https://postmarkapp.com/developer/user-guide/tracking-opens/message-opens-api" >- Message opens API</option> <option value="https://postmarkapp.com/developer/user-guide/tracking-links" >Tracking links</option> <option value="https://postmarkapp.com/developer/user-guide/managing-your-account" >Managing your account</option> <option value="https://postmarkapp.com/developer/user-guide/managing-your-account/managing-sender-signatures" >- Managing sender signatures</option> <option value="https://postmarkapp.com/developer/user-guide/managing-your-account/managing-servers" >- Managing servers</option> <option value="https://postmarkapp.com/developer/user-guide/sandbox-mode" >Sandbox mode</option> <option value="https://postmarkapp.com/developer/user-guide/sandbox-mode/server-sandbox-mode" >- Server sandbox mode</option> <option value="https://postmarkapp.com/developer/user-guide/sandbox-mode/generate-fake-bounces" >- Generate fake bounces</option> </optgroup> <optgroup label="API reference"> <option value="https://postmarkapp.com/developer/api/overview" >Overview</option> <option value="https://postmarkapp.com/developer/api/overview#endpoint-url" >- Endpoint URL</option> <option value="https://postmarkapp.com/developer/api/overview#authentication" >- Authentication</option> <option value="https://postmarkapp.com/developer/api/overview#response-codes" >- HTTP response codes</option> <option value="https://postmarkapp.com/developer/api/overview#error-codes" >- API error codes</option> <option value="https://postmarkapp.com/developer/api/email-api" >Email</option> <option value="https://postmarkapp.com/developer/api/email-api#send-a-single-email" >- Send a single email</option> <option value="https://postmarkapp.com/developer/api/email-api#send-batch-emails" >- Send batch emails</option> <option value="https://postmarkapp.com/developer/api/bulk-email" >Bulk</option> <option value="https://postmarkapp.com/developer/api/bulk-email#send-bulk-emails" >- Send bulk emails</option> <option value="https://postmarkapp.com/developer/api/bulk-email#get-a-bulk-send-status" >- Get the status/details of a bulk API request</option> <option value="https://postmarkapp.com/developer/api/bounce-api" >Bounce</option> <option value="https://postmarkapp.com/developer/api/bounce-api#delivery-stats" >- Get delivery stats</option> <option value="https://postmarkapp.com/developer/api/bounce-api#bounces" >- Get bounces</option> <option value="https://postmarkapp.com/developer/api/bounce-api#single-bounce" >- Get a single bounce</option> <option value="https://postmarkapp.com/developer/api/bounce-api#bounce-dump" >- Get bounce dump</option> <option value="https://postmarkapp.com/developer/api/bounce-api#activate-bounce" >- Activate a bounce</option> <option value="https://postmarkapp.com/developer/api/bounce-api#bounce-types" >- Bounce types</option> <option value="https://postmarkapp.com/developer/api/bounce-api#rebound-javascript-snippet-api" >- Rebound</option> <option value="https://postmarkapp.com/developer/api/templates-api" >Templates</option> <option value="https://postmarkapp.com/developer/api/templates-api#email-with-template" >- Send email with template</option> <option value="https://postmarkapp.com/developer/api/templates-api#send-batch-with-templates" >- Send batch with templates</option> <option value="https://postmarkapp.com/developer/api/templates-api#push-templates" >- Push templates to another server</option> <option value="https://postmarkapp.com/developer/api/templates-api#get-template" >- Get a template</option> <option value="https://postmarkapp.com/developer/api/templates-api#create-template" >- Create a template</option> <option value="https://postmarkapp.com/developer/api/templates-api#edit-template" >- Edit a template</option> <option value="https://postmarkapp.com/developer/api/templates-api#list-templates" >- List templates</option> <option value="https://postmarkapp.com/developer/api/templates-api#delete-template" >- Delete a template</option> <option value="https://postmarkapp.com/developer/api/templates-api#validate-template" >- Validate a template</option> <option value="https://postmarkapp.com/developer/api/server-api" >Server</option> <option value="https://postmarkapp.com/developer/api/server-api#get-server" >- Get the server</option> <option value="https://postmarkapp.com/developer/api/server-api#edit-server" >- Edit the server</option> <option value="https://postmarkapp.com/developer/api/servers-api" >Servers</option> <option value="https://postmarkapp.com/developer/api/servers-api#get-server" >- Get a server</option> <option value="https://postmarkapp.com/developer/api/servers-api#create-server" >- Create a server</option> <option value="https://postmarkapp.com/developer/api/servers-api#edit-server" >- Edit a server</option> <option value="https://postmarkapp.com/developer/api/servers-api#list-servers" >- List servers</option> <option value="https://postmarkapp.com/developer/api/servers-api#delete-server" >- Delete a server</option> <option value="https://postmarkapp.com/developer/api/message-streams-api" >Message Streams</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#list-message-streams" >- List message streams</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#get-a-message-stream" >- Get a message stream</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#edit-a-message-stream" >- Edit a message stream</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#create-a-message-stream" >- Create a message stream</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#archive-a-message-stream" >- Archive a message stream</option> <option value="https://postmarkapp.com/developer/api/message-streams-api#unarchive-a-stream" >- Unarchive a message stream</option> <option value="https://postmarkapp.com/developer/api/messages-api" >Messages</option> <option value="https://postmarkapp.com/developer/api/messages-api#outbound-message-search" >- Outbound message search</option> <option value="https://postmarkapp.com/developer/api/messages-api#outbound-message-details" >- Outbound message details</option> <option value="https://postmarkapp.com/developer/api/messages-api#outbound-message-dump" >- Outbound message dump</option> <option value="https://postmarkapp.com/developer/api/messages-api#inbound-message-search" >- Inbound message search</option> <option value="https://postmarkapp.com/developer/api/messages-api#inbound-message-details" >- Inbound message details</option> <option value="https://postmarkapp.com/developer/api/messages-api#inbound-message-bypass" >- Bypass rules for a blocked inbound message</option> <option value="https://postmarkapp.com/developer/api/messages-api#inbound-message-retry" >- Retry a failed inbound message for processing</option> <option value="https://postmarkapp.com/developer/api/messages-api#message-opens" >- Message opens</option> <option value="https://postmarkapp.com/developer/api/messages-api#opens-for-message" >- Opens for a single message</option> <option value="https://postmarkapp.com/developer/api/messages-api#message-clicks" >- Message clicks</option> <option value="https://postmarkapp.com/developer/api/messages-api#clicks-for-message" >- Clicks for a single message</option> <option value="https://postmarkapp.com/developer/api/domains-api" >Domains</option> <option value="https://postmarkapp.com/developer/api/domains-api#list-domains" >- List domains</option> <option value="https://postmarkapp.com/developer/api/domains-api#domain" >- Get domain details</option> <option value="https://postmarkapp.com/developer/api/domains-api#create-domain" >- Create domain</option> <option value="https://postmarkapp.com/developer/api/domains-api#edit-domain" >- Edit domain</option> <option value="https://postmarkapp.com/developer/api/domains-api#delete-domain" >- Delete domain</option> <option value="https://postmarkapp.com/developer/api/domains-api#domains-verify-dkim" >- Verify DKIM</option> <option value="https://postmarkapp.com/developer/api/domains-api#domains-verify-return-path" >- Verify Return-Path</option> <option value="https://postmarkapp.com/developer/api/domains-api#verify-spf" >- Verify an SPF record</option> <option value="https://postmarkapp.com/developer/api/domains-api#rotate-dkim" >- Rotate DKIM keys</option> <option value="https://postmarkapp.com/developer/api/signatures-api" >Sender signatures</option> <option value="https://postmarkapp.com/developer/api/signatures-api#list-sender-signatures" >- List sender signatures</option> <option value="https://postmarkapp.com/developer/api/signatures-api#sender-signature" >- Get sender signature</option> <option value="https://postmarkapp.com/developer/api/signatures-api#create-signature" >- Create a signature</option> <option value="https://postmarkapp.com/developer/api/signatures-api#edit-signature" >- Edit a signature</option> <option value="https://postmarkapp.com/developer/api/signatures-api#delete-signature" >- Delete a signature</option> <option value="https://postmarkapp.com/developer/api/signatures-api#resend-confirmation" >- Resend a confirmation</option> <option value="https://postmarkapp.com/developer/api/signatures-api#verify-spf" >- Verify an SPF record</option> <option value="https://postmarkapp.com/developer/api/signatures-api#request-dkim" >- Request a new DKIM</option> <option value="https://postmarkapp.com/developer/api/stats-api" >Stats</option> <option value="https://postmarkapp.com/developer/api/stats-api#overview" >- Get outbound overview</option> <option value="https://postmarkapp.com/developer/api/stats-api#sent-counts" >- Get sent counts</option> <option value="https://postmarkapp.com/developer/api/stats-api#bounce-counts" >- Get bounce counts</option> <option value="https://postmarkapp.com/developer/api/stats-api#spam-complaints" >- Get spam complaints</option> <option value="https://postmarkapp.com/developer/api/stats-api#email-tracked-count" >- Get tracked email counts</option> <option value="https://postmarkapp.com/developer/api/stats-api#email-open-counts" >- Get email open counts</option> <option value="https://postmarkapp.com/developer/api/stats-api#email-platform-usage" >- Get email platform usage</option> <option value="https://postmarkapp.com/developer/api/stats-api#email-client-usage" >- Get email client usage</option> <option value="https://postmarkapp.com/developer/api/stats-api#click-counts" >- Get click counts</option> <option value="https://postmarkapp.com/developer/api/stats-api#browser-usage" >- Get browser usage</option> <option value="https://postmarkapp.com/developer/api/stats-api#browser-platform-usage" >- Get browser platform usage</option> <option value="https://postmarkapp.com/developer/api/stats-api#click-location" >- Get click location</option> <option value="https://postmarkapp.com/developer/api/inbound-rules-triggers-api" >Triggers: Inbound rules</option> <option value="https://postmarkapp.com/developer/api/inbound-rules-triggers-api#list-triggers" >- List inbound rule triggers</option> <option value="https://postmarkapp.com/developer/api/inbound-rules-triggers-api#create-trigger" >- Create an inbound rule trigger</option> <option value="https://postmarkapp.com/developer/api/inbound-rules-triggers-api#delete-single-trigger" >- Delete a single trigger</option> <option value="https://postmarkapp.com/developer/api/webhooks-api" >Webhooks</option> <option value="https://postmarkapp.com/developer/api/webhooks-api#list-webhooks" >- List webhooks</option> <option value="https://postmarkapp.com/developer/api/webhooks-api#get-a-webhook" >- Get a webhook</option> <option value="https://postmarkapp.com/developer/api/webhooks-api#create-a-webhook" >- Create a webhook</option> <option value="https://postmarkapp.com/developer/api/webhooks-api#edit-a-webhook" >- Edit a webhook</option> <option value="https://postmarkapp.com/developer/api/webhooks-api#delete-a-webhook" >- Delete a webhook</option> <option value="https://postmarkapp.com/developer/api/suppressions-api" >Suppressions</option> <option value="https://postmarkapp.com/developer/api/suppressions-api#suppression-dump" >- Suppression dump</option> <option value="https://postmarkapp.com/developer/api/suppressions-api#create-a-suppression" >- Create a Suppression</option> <option value="https://postmarkapp.com/developer/api/suppressions-api#delete-a-suppression" >- Delete a Suppression</option> <option value="https://postmarkapp.com/developer/api/data-removals-api" >Data Removal</option> <option value="https://postmarkapp.com/developer/api/data-removals-api#create-a-data-removal-request" >- Create a Data Removal request</option> <option value="https://postmarkapp.com/developer/api/data-removals-api#check-a-data-removal-request-status" >- Check a Data Removal request status</option> </optgroup> <optgroup label="Webhooks"> <option value="https://postmarkapp.com/developer/webhooks/webhooks-overview" >Webhooks overview</option> <option value="https://postmarkapp.com/developer/webhooks/webhooks-overview#what-is-a-webhook" >- What is a webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/webhooks-overview#protecting-your-webhook" >- Protecting your webhook</option> <option value="https://postmarkapp.com/developer/webhooks/webhooks-overview#testing-your-webhook" >- Testing your webhook</option> <option value="https://postmarkapp.com/developer/webhooks/webhooks-overview#retries" >- Retry attempts</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook" >Bounce webhook</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#what-is-a-bounce-webhook" >- What is a bounce webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#bounce-webhook-data" >- Bounce webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#testing-with-curl" >- Testing with curl</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#how-you-can-use-the-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/bounce-webhook#rebound-javascript-snippet" >- Rebound</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook" >Inbound webhook</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#what-is-an-inbound-webhook" >- What is an inbound webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#inbound-webhook-data" >- Inbound webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#testing-with-curl" >- Testing with curl</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#how-you-can-use-the-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#errors-and-retries" >- Errors and retries</option> <option value="https://postmarkapp.com/developer/webhooks/inbound-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook" >Open tracking webhook</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook#what-is-an-open-webhook" >- What is an open webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook#open-webhook-data" >- Open webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook#testing-with-curl" >- Testing with curl</option> <option value="https://postmarkapp.com/developer/webhooks/open-tracking-webhook#how-you-can-use-the-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook" >Delivery webhook</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook#what-is-a-delivery-webhook" >- What is a delivery webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook#delivery-webhook-data" >- Delivery webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook#testing-with-curl" >- Testing with curl</option> <option value="https://postmarkapp.com/developer/webhooks/delivery-webhook#how-you-can-use-the-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook" >Click webhook</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook#what-is-a-click-webhook" >- What is a click webhook?</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook#click-webhook-data" >- Click webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook#testing-with-curl" >- Testing with curl</option> <option value="https://postmarkapp.com/developer/webhooks/click-webhook#how-you-can-use-the-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook" >Spam complaint webhook</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook#what-is-a-spam-complaint" >- What is a spam complaint?</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook#set-the-webhook-url" >- Set the webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook#spam-complaint-webhook-data" >- Spam complaint webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook#testing-the-spam-complaint-webhook-with-curl" >- Testing the spam complaint webhook with curl</option> <option value="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook#how-you-can-use-the-spam-complaint-data" >- How you can use the data</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook" >Subscription change webhook</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook#what-is-a-subscription-change" >- What is a subscription change?</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook#set-the-subscription-change-webhook-url" >- Set the subscription change webhook URL</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook#subscription-change-webhook-data" >- Subscription change webhook data</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook#testing-the-subscription-change-webhook-with-curl" >- Testing the subscription change webhook with curl</option> <option value="https://postmarkapp.com/developer/webhooks/subscription-change-webhook#how-you-can-use-the-subscription-change-data" >- How you can use the subscription change data</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error" >SMTP API Error</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error#what-is-an-smtp-api-error" >- What is an SMTP API Error</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error#set-smtp-api-errors-for-a-server" >- Set SMTP API Errors for a Server</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error#smtpi-api-error-data" >- SMTP API Error Data</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error#testing-the-smtp-api-error" >- Testing the SMTP API Error</option> <option value="https://postmarkapp.com/developer/webhooks/smtp-api-error#how-can-you-use-smtp-api-error" >- How can you use SMTP API Error</option> </optgroup> </select> </div> <section class="docs-content docs-content--2-col"> <!-- Docs Section --> <div class="docs-section docs-section--title"> <div class="docs-description"> <h1>Introduction</h1> </div> </div> <!-- End Docs Section --> <!-- Docs Section --> <div class="docs-section"> <div class="docs-description"> <p>Postmark helps deliver and track application email. In a nutshell, the service replaces SMTP (or Sendmail) with a far more reliable, scalable and care-free environment. In addition, you can track statistics such as number of emails sent or processed, opens, bounces and spam complaints.</p> <h3>Things you should know</h3> <ul><li><strong>Postmark separates emails by Message Streams</strong>. Transactional Message Streams are for one to one emails triggered by a user action like a welcome email, password reset, or order confirmation. Newsletters, announcements, or any other bulk email can be sent through Broadcast Message Streams. If you’re uncertain if your email qualifies as Transactional or Broadcast, you can always <a href="https://postmarkapp.com/support">contact support</a> and we’ll review your usage.</li><li><strong>A confirmed email address is required to start sending.</strong> Before you can start sending emails, you will need to verify the email address you send from in our <a href="https://account.postmarkapp.com/signatures">Signatures section</a>.</li><li><strong>Maximum email size is 10 MB.</strong> This includes email content, headers, and attachments. You will receive an error if your emails are too large.</li><li><strong>Postmark will only accept attachments with specific file types</strong>, so please review our <a href="https://postmarkapp.com/developer/user-guide/send-email-with-api#attachments">list of accepted file types</a>. We also support <a href="https://postmarkapp.com/developer/user-guide/send-email-with-api#inline-image-attachments">inline image embedding</a>.</li><li><strong>The maximum number of recipients for each email is 50</strong>, including all To, CC, and BCC recipients. Each recipient counts as a single Postmark email or a single Postmark credit for older accounts.</li></ul> <h3>Get started</h3> <div class="u-grid u-margin-bottom--s u-grid--gutters-medium intro-list"> <div class="u-grid-cell"> <h4>Integration</h4> <p>Get up and running with an existing Postmark library. This is the fastest way to start sending email with Postmark without having to write your own code.</p> <ul class="index-list"> <li><a href="https://postmarkapp.com/developer/integration/official-libraries">Official Postmark libraries →</a></li> <li><a href="https://postmarkapp.com/developer/integration/community-libraries">Community libraries →</a></li> <li><a href="https://postmarkapp.com/developer/integration/other-tools-and-integrations">Other tools and integrations →</a></li> </ul> </div> <div class="u-grid-cell"> <h4>User guide</h4> <p>User guides provide a detailed walk through on accomplishing specific tasks with Postmark. We recommend this if you’re just getting started.</p> <ul class="index-list"> <li><a href="https://postmarkapp.com/developer/user-guide/send-email-with-api">Sending email with API →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/send-email-with-smtp">Sending email with SMTP →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/inbound">What is inbound processing? →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/tracking-opens">Tracking opens →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/tracking-links">Tracking links →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/managing-your-account">Managing your account →</a></li> <li><a href="https://postmarkapp.com/developer/user-guide/sandbox-mode">Sandbox mode →</a></li> </ul> </div> </div> <div class="u-grid u-grid--gutters-medium intro-list"> <div class="u-grid-cell col"> <h4>API reference</h4> <p>Get straight to the details of every HTTP request available through Postmark’s REST API.</p> <ul class="index-list"> <li><a href="https://postmarkapp.com/developer/api/overview">Overview →</a></li> <li><a href="https://postmarkapp.com/developer/api/email-api">Email API →</a></li> <li><a href="https://postmarkapp.com/developer/api/bulk-email">Bulk Email →</a></li> <li><a href="https://postmarkapp.com/developer/api/bounce-api">Bounce API →</a></li> <li><a href="https://postmarkapp.com/developer/api/templates-api">Templates API →</a></li> <li><a href="https://postmarkapp.com/developer/api/server-api">Server API →</a></li> <li><a href="https://postmarkapp.com/developer/api/servers-api">Servers API →</a></li> <li><a href="https://postmarkapp.com/developer/api/message-streams-api">Message Streams API →</a></li> <li><a href="https://postmarkapp.com/developer/api/messages-api">Messages API →</a></li> <li><a href="https://postmarkapp.com/developer/api/domains-api">Domains API →</a></li> <li><a href="https://postmarkapp.com/developer/api/signatures-api">Sender signatures API →</a></li> <li><a href="https://postmarkapp.com/developer/api/stats-api">Stats API →</a></li> <li><a href="https://postmarkapp.com/developer/api/inbound-rules-triggers-api">Inbound rules triggers API →</a></li> <li><a href="https://postmarkapp.com/developer/api/webhooks-api">Webhooks API →</a></li> <li><a href="https://postmarkapp.com/developer/api/suppressions-api">Suppressions API →</a></li> <li><a href="https://postmarkapp.com/developer/api/data-removals-api">Data Removal API →</a></li> </ul> </div> <div class="u-grid-cell col"> <h4>Webhooks</h4> <p>Receive instant notifications to your application when specific events occur. Data is posted to your application in a neatly packaged JSON object.</p> <ul class="index-list"> <li><a href="https://postmarkapp.com/developer/webhooks/webhooks-overview">Webhooks overview →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/bounce-webhook">Bounce webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/inbound-webhook">Inbound webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/open-tracking-webhook">Open tracking webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/delivery-webhook">Delivery webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/click-webhook">Click webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/spam-complaint-webhook">Spam complaint webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/subscription-change-webhook">Subscription change webhook →</a></li> <li><a href="https://postmarkapp.com/developer/webhooks/smtp-api-error">SMTP API Error →</a></li> </ul> </div> </div> </div> </div> <!-- End Docs Section --> </section> </div> </div> <footer class="footer footer--developer-docs"> <div class="u-container footer_container"> <nav class="nav nav--footer " role="navigation" aria-label="Footer"> <div class="nav_group"> <h4 class="nav_heading">Product</h4> <ul class="nav_list"> <li class="nav_item"> <a href="https://postmarkapp.com/pricing" class="nav_link">Pricing</a> </li> <li class="nav_item"> <a href="https://postmarkapp.com/customers" class="nav_link">Customers</a> </li> <li class="nav_item"> <a href="https://postmarkapp.com/reviews" class="nav_link">Reviews</a> </li> <li class="nav_item"> <a href="https://postmarkapp.com/dedicated-ips" class="nav_link">Dedicated IPs</a> </li> <li class="nav_item"> <a href="https://postmarkapp.com/ios" class="nav_link">iOS App</a> </li> <li class="nav_item"> <a 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