Email & Messaging API Key

Postmark REST API

Transactional email delivery for web applications

Postmark is a fast and reliable transactional email service designed for web applications. It provides developers with powerful APIs to send application emails, track delivery, manage templates, and analyze email performance with detailed analytics. Postmark focuses on deliverability, speed, and developer experience with comprehensive webhooks and monitoring tools.

Base URL https://api.postmarkapp.com

API Endpoints

Method	Endpoint	Description
POST	`/email`	Send a single email message with optional attachments and tracking
POST	`/email/batch`	Send up to 500 email messages in a single API call
POST	`/email/withTemplate`	Send an email using a predefined template with dynamic content
POST	`/email/batchWithTemplates`	Send multiple templated emails in a single batch request
GET	`/messages/outbound`	Retrieve a list of sent outbound messages with filters and pagination
GET	`/messages/outbound/{messageid}/details`	Get detailed information about a specific sent message including opens and clicks
GET	`/messages/inbound`	Retrieve inbound messages received by your server
GET	`/bounces`	List bounced emails with filtering options by type and date range
GET	`/bounces/{bounceid}`	Get details about a specific bounce event
PUT	`/bounces/{bounceid}/activate`	Activate a bounced email address to allow future sending
GET	`/templates`	List all email templates in your account with metadata
POST	`/templates`	Create a new email template with HTML and text versions
GET	`/templates/{templateIdOrAlias}`	Get a specific template by ID or alias including content and settings
PUT	`/templates/{templateIdOrAlias}`	Update an existing email template's content or settings
DELETE	`/templates/{templateIdOrAlias}`	Delete an email template permanently
POST	`/templates/validate`	Validate template syntax and test with sample data before sending
GET	`/stats/outbound`	Get outbound email statistics including sent, bounced, and opened counts
GET	`/stats/outbound/opens`	Retrieve detailed email open tracking statistics with platform breakdown
GET	`/stats/outbound/clicks`	Get click tracking statistics for links in sent emails
GET	`/deliverystats`	Access comprehensive delivery statistics and inbox placement data
GET	`/suppressions/dump`	Export the complete suppression list for your server
POST	`/suppressions`	Add email addresses to the suppression list to prevent sending
DELETE	`/suppressions/{emailaddress}`	Remove an email address from the suppression list
GET	`/webhooks`	List all configured webhook endpoints for event notifications
POST	`/webhooks`	Create a new webhook to receive real-time email event notifications

Code Examples

curl -X POST "https://api.postmarkapp.com/email" \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -H "X-Postmark-Server-Token: your-server-token" \
  -d '{
    "From": "sender@example.com",
    "To": "recipient@example.com",
    "Subject": "Hello from Postmark",
    "TextBody": "This is a plain text message",
    "HtmlBody": "<html><body><h1>Hello!</h1><p>This is an HTML message</p></body></html>",
    "MessageStream": "outbound",
    "TrackOpens": true,
    "TrackLinks": "HtmlAndText"
  }'

const sendEmail = async () => {
  const response = await fetch('https://api.postmarkapp.com/email', {
    method: 'POST',
    headers: {
      'Accept': 'application/json',
      'Content-Type': 'application/json',
      'X-Postmark-Server-Token': 'your-server-token'
    },
    body: JSON.stringify({
      From: 'sender@example.com',
      To: 'recipient@example.com',
      Subject: 'Hello from Postmark',
      TextBody: 'This is a plain text message',
      HtmlBody: '<html><body><h1>Hello!</h1><p>This is an HTML message</p></body></html>',
      MessageStream: 'outbound',
      TrackOpens: true,
      TrackLinks: 'HtmlAndText'
    })
  });
  
  const data = await response.json();
  console.log('Message sent:', data.MessageID);
  return data;
};

sendEmail();

import requests

url = 'https://api.postmarkapp.com/email'
headers = {
    'Accept': 'application/json',
    'Content-Type': 'application/json',
    'X-Postmark-Server-Token': 'your-server-token'
}

payload = {
    'From': 'sender@example.com',
    'To': 'recipient@example.com',
    'Subject': 'Hello from Postmark',
    'TextBody': 'This is a plain text message',
    'HtmlBody': '<html><body><h1>Hello!</h1><p>This is an HTML message</p></body></html>',
    'MessageStream': 'outbound',
    'TrackOpens': True,
    'TrackLinks': 'HtmlAndText'
}

response = requests.post(url, json=payload, headers=headers)
data = response.json()
print(f"Message sent: {data['MessageID']}")

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send_email Send transactional emails with template support, tracking, and attachments through natural language requests

check_delivery_status Query email delivery status, opens, clicks, and bounce information for sent messages

manage_templates Create, update, list, and validate email templates with dynamic content variables

analyze_email_stats Retrieve and analyze email performance metrics including delivery rates, opens, and engagement

manage_suppressions Add, remove, and query email addresses on the suppression list to manage recipient preferences

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Postmark REST API

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Code Examples

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