Webhooks Explained: Connecting Your Platform to the Rest of Your Stack
5 min read
A webhook is a way for your marketing automation platform to send data to another system the moment something happens. When a contact submits a form, reaches a lead score threshold, or unsubscribes, a webhook can fire and notify another tool in real time. This is how integrations that feel seamless are built.
How Webhooks Work
When a defined event occurs in your platform, it sends an HTTP POST request to a URL you specify - the webhook endpoint. That URL belongs to another service: your CRM, a Slack notification app, a Zapier automation, a custom script. The receiving service reads the data in the request and takes action: creates a contact, sends a notification, updates a record.
Common Webhook Use Cases
- Push new leads from a landing page form into your CRM instantly
- Notify a Slack channel when a contact reaches the sales-ready score threshold
- Update a contact's status in a support tool when they submit a specific form
- Trigger a Zapier workflow that adds a row to a Google Sheet for reporting
- Send a contact's data to an SMS provider when they opt into text messages
Inbound vs. Outbound Webhooks
Your platform can both send and receive webhooks. Outbound webhooks send data from your platform to external tools. Inbound webhooks (sometimes called webhook listeners) receive data from external tools and update contact records or trigger automations. A purchase on your e-commerce site can fire an inbound webhook that tags the contact as a customer and starts a post-purchase automation.
Testing and Debugging Webhooks
Services like webhook.site let you capture and inspect webhook payloads without building a real endpoint. Use this during setup to confirm the data structure before connecting to your actual destination. Most platforms also show a webhook delivery log - check it when a webhook is not behaving as expected to see the response code and any error messages.