Webhook

What Is a Webhook?

A webhook is an automated notification that one system sends to another when something specific happens. Instead of constantly checking for updates (called polling), the source system pushes data to a URL you specify the moment an event occurs. It is sometimes called a "reverse API" — instead of you asking for data, the data comes to you.

In simple terms: if an API is like checking your mailbox every five minutes, a webhook is like getting a doorbell ring the instant a package arrives.

WordPress core does not include a built-in webhook system, but WooCommerce has full webhook support. You can configure webhooks at WooCommerce > Settings > Advanced > Webhooks to fire when specific events happen:

• Order created, updated, or deleted
• Product created, updated, or deleted
• Customer created, updated, or deleted
• Coupon created, updated, or deleted

You can also hook into any WooCommerce action — for example, woocommerce_add_to_cart fires a webhook every time a customer adds an item to their cart.

When you set up a webhook, you provide:

• Name — A label for your reference
• Status — Active, Paused, or Disabled
• Topic — The event that triggers the notification
• Delivery URL — The external endpoint that receives the data (e.g., Zapier, Slack, your custom server)
• Secret — A key used to generate an HMAC-SHA256 hash so the receiver can verify the message is authentic

When the event fires, WooCommerce sends a JSON payload to your delivery URL. A successful delivery is any 2xx, 301, or 302 response. After 5 consecutive failed deliveries, the webhook is automatically disabled to prevent spam.

Webhooks in Practice

Webhooks are the backbone of modern e-commerce integrations. Common use cases include:

• Sending new orders to a fulfillment service (ShipStation, ShipBob)
• Notifying your team in Slack when a high-value order comes in
• Syncing customer data to a CRM like HubSpot or Mailchimp
• Triggering automations in Zapier or Make (Integromat) based on WooCommerce events

For non-WooCommerce WordPress sites, plugins like WP Webhooks and AutomatorWP add webhook functionality, letting you trigger notifications on post publish, user registration, form submissions, and more.

Why It Matters

Webhooks enable real-time communication between your WordPress site and the rest of your tech stack. Without them, you would need to constantly poll APIs for changes — which is slower, more expensive, and wastes server resources. If you run a WooCommerce store or integrate WordPress with third-party tools, understanding webhooks is essential for building efficient, automated workflows.

Sources

• Webhooks Documentation — WooCommerce
• Working with Webhooks — WooCommerce Developer Docs