Webhook Studio
Build, HMAC-sign and send webhooks — even to localhost, no relay
Description
A complete webhook workbench right inside your browser. JSON payload editor (with sorted-key canonicalization), custom headers, a secret for HMAC-SHA256 signing computed locally via Web Crypto, and a direct fetch to any endpoint, including http://localhost. Unlike webhook.site, no data passes through an external relay: the request goes straight from your browser to the endpoint you choose. Optional signed timestamp (Stripe-style ts.body scheme), hex or base64 signature encoding, configurable signature header, and a view of response status, timing and body. Draft (payload, headers, secret) stored locally only. Zero telemetry.
Features
- JSON payload editor with validation and sorted-key canonicalization (stable signature)
- HMAC-SHA256 signature computed locally via Web Crypto (secret never sent in clear to third parties)
- Direct fetch send to any endpoint, including http://localhost — no external relay
- Custom headers (Name: value per line) with case-insensitive merge
- Selectable signature encoding: hex or base64, with configurable signature header
- Optional signed timestamp using the ts.body scheme (Stripe-style) and a dedicated header
- POST/PUT/PATCH/DELETE/GET methods and a view of status, response time and body
- Draft (payload, headers, secret) stored locally only, zero telemetry
Privacy
100% local processing in your browser. Zero telemetry: no data is sent to external servers.
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Screenshots
