Webhook vs WebSocket: What's the Difference?
Webhooks and WebSockets both deliver real-time data, but one is a short one-way HTTP callback and the other a persistent two-way connection. A clear comparison of webhook vs WebSocket, when to use each, and how they work together.
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.