Test Slack Webhooks with HookTest
Test Slack webhooks and event subscriptions for bot and app development. Use HookTest to create a free webhook URL, point Slack at it, and inspect every request in real time — headers, body, and signature included.
Quick Start
Get Slack webhooks flowing to HookTest in under a minute:
- Create a HookTest URL. Go to hooktest.dev and click Create Bin. Copy the webhook URL.
- Add it to Slack webhook settings. Paste the HookTest URL as your webhook endpoint in the Slack developer dashboard. Select the events you want to receive.
- Trigger an event and inspect. Perform an action in Slack (or use their test/sandbox mode) and watch the request appear in HookTest in real time. Check headers, body, and query parameters.
Common Slack Webhook Events
These are the most commonly tested Slack webhook events. Each one triggers an HTTP POST to your webhook URL with a JSON payload.
| Event | Description |
|---|---|
message | A message is posted to a channel |
app_mention | Your app is mentioned |
reaction_added | A reaction emoji is added |
channel_created | A new channel is created |
Verifying Slack Signatures
Slack signs every webhook request using the X-Slack-Signature header. You should always verify this signature in production to confirm the request actually came from Slack and was not tampered with in transit.
When testing with HookTest, you can inspect the raw signature header value in the request details. This is useful for verifying that your signature verification code handles the header format correctly before deploying to production.
See the official Slack webhook docs for the full signature verification algorithm and code samples.
Why Test Slack Webhooks?
Webhook handlers are notoriously hard to debug. You cannot see what Slack is sending until your endpoint receives it, and errors in your handler can cause silent failures — missed payments, lost data, or broken integrations.
HookTest gives you full visibility into every request before you write a line of handler code. Create a bin, point Slack at it, and see exactly what arrives: HTTP method, headers (including signatures), body, and query parameters. Once your handler is ready, use webhook forwarding to send requests to your local server in real time.
Start testing Slack webhooks
Create a free webhook URL in one click. No signup required.
Create Free Webhook URL