Webhook
Definition
A webhook is a message one app sends to a web address you choose the moment something happens, such as a form being submitted or a payment going through. It lets another system react straight away instead of checking for changes on a timer.
By Ronan Liedmeier, fractional head of growth and course author · Published 17 October 2026 · Last updated 17 October 2026
Also called: HTTP callback
Most event-driven automations start with one. If you want a lead routed or an order processed within seconds of it arriving, a webhook is how the first app tells the second.
How it differs from an API call
With a normal API call, your system asks the other service for new data, for example every 15 minutes. With a webhook, the other service tells your system when something new exists, so nothing runs when nothing has changed.
In an automation tool you add a webhook trigger, copy the URL it gives you and paste it into the source app's settings. Each event then sends its data, usually as JSON, to that URL and starts the workflow. In n8n, for example, the Webhook node gives you a test URL that shows incoming data in the editor while you build, and a production URL that goes live once you publish the workflow.
Example
A yoga studio owner wants new members welcomed the moment they pay. Her payment provider sends a webhook for each successful payment to her automation tool. The workflow adds the member to the booking system, sends the welcome email and posts the name in the staff Slack channel, all within a minute of checkout.
Common mistake
Leaving the webhook URL open to anyone. A person who finds the address can send fake events and run your workflow. Require a secret header or signature check, or limit the URL to known IP addresses. The n8n Webhook node, for instance, supports header and JWT authentication and an IP allowlist.
Learn it in AI Academy
- Orchestration: n8n at DepthExpert · 9 min
- No-Code Automation: Zapier & MakeBeginner · 12 min
Related terms
- API (application programming interface)
- An API (application programming interface) is a set of requests a software service agrees to accept from other programs, a bit like a menu. A program sends a request such as "create a contact" and the service sends back data or a confirmation.
- No-code automation
- No-code automation is building workflows that move data between apps by connecting visual blocks instead of writing code. Each workflow starts with a trigger, like a new email, and runs a set of steps, like creating a task, every time that trigger fires.
- n8n
- n8n is a workflow automation tool where you build automations by linking steps, called nodes, on a visual canvas, starting from a trigger such as a schedule or an incoming webhook. Workflows can include AI steps and can run on n8n's cloud or on your own server.