StreamLive Pro

What is a webhook? A web address that receives messages

What a webhook is: a private web address that gets a message when something happens. Incoming webhooks in Discord and Slack, event webhooks, and how to keep them safe.

Updated November 5, 2026 · 6 min read

A webhook is a web address that waits for messages. Instead of an app asking another app again and again "did anything happen?", the second app sends a short message to the webhook address the moment something happens. The address is usually long and random, and whoever knows it can send to it, so a webhook address should be treated like a password.

Webhooks go in two directions, and it helps to keep them apart:

• Incoming webhook: an address that a service such as Discord or Slack creates for one channel. Anything posted to it appears in that channel. Slack describes its incoming webhooks as "a way to post messages from apps into Slack" (Slack: Sending messages using incoming webhooks, checked 5 November 2026).
• Outgoing (event) webhook: an address you own, on your own server, that a service calls when an event happens: a payment went through, a broadcast started.

Everyday examples

Webhooks run quietly behind many things you already use. For example:

• A shop and its payment provider. When a customer pays, the payment provider sends a webhook to the shop, and the order is marked paid at once.
• A form and a spreadsheet. When someone submits a sign-up form, a webhook sends the answers to a sheet or a mailing list.
• A team chat. A monitoring service posts "the website is down" into a Slack channel through an incoming webhook.
• A broadcast and a community. When your live starts, a message lands in your Discord server so members know to join.

In each case nobody presses a button to pass the news along. The first system knows something happened and tells the second one immediately.

Webhook compared with the alternatives

What a webhook message looks like

A webhook message is an ordinary web request, usually with a small block of JSON text:

POST https://example.com/hooks/streamlive
Content-Type: application/json

{"event": "stream.started", "data": {"stream_id": "...", "title": "Weekly class"}}

The receiving side reads the event name, does its job (posts a message, updates a sheet, starts a recording) and answers quickly that it received it.

Webhooks in StreamLive Pro

1. Posting to Discord and Slack (incoming webhooks). These two connect through a webhook instead of a sign-in. You create a webhook for one channel in Discord or Slack, paste its address into Connections, and the channel becomes a destination on Publish everywhere. When you connect Discord, the address is checked with Discord first; connecting Slack sends nothing to the channel. Discord takes text and one file; Slack takes text and links but no files. Step by step: Post to a Discord or Slack channel with a webhook.

2. Event webhooks (outgoing), on the Studio plan. In Settings, the "API & Webhooks" section has a Webhooks card: you type an https address, tick the events you want, and click "Add webhook". StreamLive Pro then sends a POST to that address on every event you ticked, signed with HMAC-SHA256. The signing secret is shown once, right after you add the webhook, so copy it then. The same card lists your webhooks and lets you delete them. On other plans the section explains that webhooks come with Studio: /pricing?lang=en.

The first three are ticked by default. Each event is sent once, with no retry, and a webhook that fails 20 times in a row is switched off. Rules that protect you: the address must be https and must point to a public server, not an internal one; there can be up to 10 per account; redirects are not followed. API keys are in the same section: API keys for developers: create, use and revoke.

Webhook or polling

A webhook pushes a message to you the moment something happens. Polling is the other way round: your system asks the service every few minutes whether anything changed. Polling is simpler to set up, needs no public address on your side, and nothing is lost if your server was down for a while, because you simply ask again. Its cost is delay and extra requests. A webhook is instant and quiet, but your server must be reachable, must answer quickly and must cope with a message arriving twice or not at all, so careful systems also poll now and then to catch anything missed. With StreamLive Pro you can do both: event webhooks on the Studio plan, and the API for anything you want to ask on your own schedule.

Keeping a webhook safe

1. Treat the address as a secret. Anyone who has an incoming webhook address can post into your channel. Do not paste it in public chats, screenshots or shared documents.
2. Use one webhook per purpose. If one leaks, you delete only that one.
3. Delete and recreate a leaked webhook. In Discord and Slack you can delete a webhook and make a new one; then paste the new address in Connections.
4. On your own server, check the signature. Reject messages whose signature does not match, and answer quickly; do slow work after replying.
5. Expect repeats and gaps. Design the receiving side so that receiving the same event twice does no harm.

Before you create a webhook

1. Decide which channel should receive the posts. A webhook belongs to one channel; a second channel needs its own webhook.
2. Check you have the right permission. In Discord that is managing the channel's integrations; in Slack, adding an app to the workspace. If you do not see the option, ask the admin.
3. Name the webhook clearly, for example "StreamLive Pro posts", so the admin knows what it is in a year.
4. Paste it once and do not share it further.

Common problems

Frequently asked questions

What is a webhook in simple words?

A private web address that receives a message automatically when something happens, so nobody has to keep checking.

Is a webhook URL secret?

Yes. Anyone who has an incoming webhook address can post to that channel. Keep it private and delete it if it leaks.

How do I post from StreamLive Pro to Discord?

Create a webhook in the Discord channel settings, paste its address in Connections, and choose the channel when you publish.

Can StreamLive Pro notify my own system when a live starts?

Yes, on the Studio plan: in Settings, "API & Webhooks", add your https address with the stream.started event. Messages are signed with a secret shown once, so your server can check they came from StreamLive Pro.

Keep reading