Back to Glossary
Tools & Platforms

Webhook

An automated HTTP callback that sends real-time data when email events occur, enabling system integration.

Definition

A webhook is an automated HTTP callback that sends data to a specified URL when certain events occur. In email marketing, webhooks notify your systems in real-time when emails are sent, delivered, opened, clicked, bounced, or when subscribers take actions. This enables integration with CRMs, analytics tools, and custom applications.

Why It Matters

Webhooks enable real-time system integration and automation. Instead of polling for updates, your systems receive instant notifications. This powers real-time dashboards, instant CRM updates, triggered workflows, and custom analytics. Webhooks are essential for sophisticated email marketing operations.

How It Works

You configure a webhook URL in your email platform. When specified events occur (email opened, link clicked, etc.), the platform sends an HTTP POST request to your URL containing event data. Your server processes this data to update systems, trigger actions, or log analytics.

Example

Webhook data for email click event:

{ "event": "click", "timestamp": "2024-01-15T10:30:00Z", "email": "[email protected]", "campaign_id": "camp_123", "link_url": "https://yoursite.com/product", "user_agent": "Mozilla/5.0...", "ip_address": "192.168.1.1" }

Your server receives this instantly when the click occurs.

Best Practices

  • 1Use secure HTTPS endpoints for webhooks
  • 2Implement authentication for webhook validation
  • 3Handle webhook failures gracefully with retries
  • 4Process webhooks asynchronously for reliability
  • 5Monitor webhook health and latency

Frequently Asked Questions

APIs require you to request data (pull). Webhooks push data to you when events occur. APIs are for on-demand queries; webhooks are for real-time notifications. Most integrations use both - webhooks for real-time events, APIs for data queries.

Good ESPs retry failed webhooks with exponential backoff. Implement logging to catch missed events. Build idempotent handlers that can process the same event twice safely. Have a recovery process for missed events.