WebSocket Opening Handshake Workbench
Calculate a WebSocket accept value from a supplied key and compare an optional server accept field locally.
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How to use WebSocket Opening Handshake Workbench
Calculate a WebSocket accept value from a supplied key and compare an optional server accept field locally. The calculation hashes the Base64 key text followed by the RFC 6455 GUID; it does not hash decoded key bytes. A matching value is one handshake condition, not a connection or origin-trust verdict.
- Provide sec-websocket-key, optional sec-websocket-accept.
- Choose the supported mode and run the tool. Review its assumptions and any reported errors.
- Copy the result or download a separate output; reset to clear the current form.
Good to know
- Canonical padded Base64 key must decode to 16 bytes. Comparison is exact; surrounding header whitespace must be removed explicitly.
- No WebSocket is opened and no request, Origin, Upgrade, Connection, subprotocol, extension or TLS validation is performed. SHA-1 is required here for protocol compatibility, not file integrity or authentication.
- Inputs are processed on this device and are not automatically saved or uploaded.
Common questions
Does a matching accept field prove the server is secure?
No. It checks only the RFC 6455 challenge calculation for the supplied key. Network, origin and application authorization checks are separate.
Does this change my original input?
No. The tool returns a separate result. Review that output before using it in another application.
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