Webhook vs WebSocket: What's the Difference?
Webhooks and WebSockets both deliver real-time data, but one is a short one-way callback and the other a persistent connection. When to use each.
Both webhooks and WebSockets are ways to get data in near real time instead of polling — but they're built for different jobs. One is a brief one-directional HTTP callback; the other is a long-lived two-way pipe.
The one-line answer
- Webhook: a server sends you a single HTTP POST when an event happens, then the connection closes. Great for server-to-server event notifications.
- WebSocket: a persistent, two-way connection stays open so either side can send messages at any time. Great for live, bidirectional communication — usually browser ↔ server.
How a webhook works
A webhook is an ordinary HTTP request. You register a URL with a provider, and they POST to it the moment something happens — then it's done. (New to them? See what is a webhook.)
POST /your-webhook-endpoint
Content-Type: application/json
{ "event": "payment.succeeded", "id": "pi_123" }
There's no connection to keep alive. It's stateless, one-way (provider → you), and each event is an independent request the provider can retry if it fails.
How a WebSocket works
A WebSocket starts as an HTTP request that "upgrades" into a persistent TCP connection which stays open. After the handshake, both sides can push messages whenever they like, with very little per-message overhead:
Client --- handshake (HTTP Upgrade) ---> Server
Client <========= open connection ========> Server
(either side sends messages any time)
That open channel is what makes WebSockets great for chat, multiplayer, live dashboards and collaborative editing — but it also means you have to manage connection state, reconnects and scaling those long-lived connections.
Webhook vs WebSocket at a glance
| Webhook | WebSocket | |
|---|---|---|
| Connection | Short-lived HTTP request per event | Persistent, always-open |
| Direction | One-way (server → you) | Two-way (full duplex) |
| Who connects | Provider POSTs to your URL | Client opens the connection to a server |
| Best for | Server-to-server event notifications | Live browser ↔ server messaging |
| Overhead | New request each event | One connection, low per-message cost |
| Delivery on failure | Provider retries the POST | You handle reconnection & missed messages |
| Needs a public URL | Yes — a URL the provider can reach | No — the client dials out |
| Typical examples | Stripe payments, GitHub pushes, CI/CD | Chat, live dashboards, multiplayer |
When to use which
Reach for a webhook when:
- One backend needs to tell another backend that an event happened (a payment, a deploy, a new record).
- You want the provider to own delivery and retries.
- You don't want to maintain an always-on connection.
Reach for a WebSocket when:
- A browser (or client) needs live updates and needs to send data back.
- You're streaming many messages continuously and want minimal per-message overhead.
- Latency on a steady stream matters — chat, presence, live prices, collaborative UIs.
They're better together
A very common architecture uses both: your server receives webhooks from providers, then fans the relevant updates out to connected browsers over WebSockets.
Stripe --webhook--> your backend --WebSocket--> user's browser (live "payment received!")
The webhook is the reliable server-to-server event; the WebSocket is the live last hop to the UI.
The catch with webhooks: you need a reachable URL
Unlike a WebSocket, where the client dials out, a webhook needs a public URL the provider can POST to — awkward when your handler runs on localhost or behind a firewall. That's what Webhook Relay solves: inspect the payload in your browser, then forward it to localhost or a private server with no public IP.
For the related comparison, see webhooks vs API. Ready to try one? Test a webhook now or start forwarding for free.