Webhooks
In short
A webhook is an HTTP request that one system sends automatically to a URL you specify when a defined event occurs, such as a form submission or a deal changing stage. The receiving system gets the event data immediately and can act on it.
Webhooks are often described as reverse APIs. With a normal API you ask for data; with a webhook the data is pushed to you. This makes them the standard way to move events between CRMs, enrichment tools, and automation platforms in real time.
How webhooks work
Setup follows a few steps.
- Register: Give the sending app a destination URL and choose the events to subscribe to.
- Event fires: The app sends a POST request, usually with a JSON payload describing the event.
- Receive and respond: Your endpoint processes the payload and returns a success status.
- Retry: Many senders retry if the endpoint does not respond successfully.
GTM examples
Say a prospect fills out a demo form. A webhook sends the lead to an enrichment service, which returns company size and industry. A second webhook posts the enriched record to the CRM and alerts the right rep in chat. The lead is routed in seconds instead of waiting for a nightly sync.
Other common triggers include new signups, meeting booked, deal closed, email replied, and enrichment job finished.
Webhooks vs. API polling
- Webhooks: Push on event. Fast and efficient, but you must run an endpoint that is always available.
- Polling: Your system asks repeatedly on a schedule. Simpler to control, but slower and wasteful when nothing changed.
Common mistakes
- No verification: Check signatures or secrets so you only accept genuine requests.
- No idempotency: Retries can deliver the same event twice. Deduplicate by event ID.
- Slow handlers: Acknowledge quickly and process in the background to avoid timeouts.
- No monitoring: Log failures and alert on them, or leads silently disappear.
When to use them
Use webhooks when speed matters and the source supports them. Use polling or batch syncs for bulk historical loads or sources without event support.
Webhooks FAQs
What is a webhook in simple terms?
A webhook is an automatic message one app sends to another when something happens, like a new form submission. Instead of repeatedly asking for updates, the receiving app gets notified instantly at a URL you provide.
What is the difference between a webhook and an API?
An API is something you call to request or send data when you choose. A webhook is sent to you by another system when an event occurs. Many integrations use both: webhooks for notifications and APIs for fetching details.
How do webhooks help sales and marketing teams?
They move events between tools in real time. A signup, reply, or form fill can trigger enrichment, lead routing, CRM updates, and rep alerts within seconds, which shortens response time and reduces manual data entry.
How do I secure a webhook endpoint?
Use HTTPS, verify the signature or shared secret sent with each request, reject unexpected sources, and deduplicate events by ID. Respond quickly and process the payload asynchronously so retries do not cause duplicate actions.
