← Glossary

What is a Webhook?

A webhook is an automated HTTP callback that sends real-time data from one application to another when a specific event occurs, enabling instant communication between systems without the receiving application needing to continuously check (poll) for updates.

The easiest way to understand webhooks is to compare them with APIs. With a standard API, your application asks another service "has anything changed?" repeatedly, say every 30 seconds. Most of the time the answer is "no," and the request was wasted. A webhook flips this model: instead of you asking, the other service tells you when something happens. It sends an HTTP POST request to a URL you specify, containing the event data. No polling, no wasted requests, no delay.

For example, when Stripe processes a payment, it can send a webhook to your server with the payment details. When a GitHub repository receives a push, it can notify your deployment system via webhook. When a social media platform processes a scheduled post, it can confirm publication through a webhook callback.

How Webhooks Work

Setting up a webhook involves three steps. First, you create an endpoint on your server -- a URL that can receive incoming HTTP POST requests. Second, you register that URL with the service you want to receive events from, specifying which events you care about. Third, when the event occurs, the service sends an HTTP request to your URL with a JSON payload containing the event details. Your server processes the payload and takes whatever action is needed.

Security is important with webhooks because anyone could potentially send requests to your endpoint. Most services include a signature or secret token with each webhook so your server can verify the request came from the legitimate source. Always validate webhook signatures before processing the payload.

Webhooks in Social Media

In social media tools, webhooks enable real-time workflows. A common pattern is triggering a social media post when a blog article is published -- the CMS sends a webhook to the scheduling tool, which creates and queues a post about the new article. Another example is receiving real-time notifications when a scheduled post is successfully published or when it fails. Without webhooks, you would have to check each platform manually to confirm publication.