JWT Debugger
Decode and inspect JSON Web Tokens locally. Review headers and payloads without sending the token elsewhere.
Security note
JWT payload is only Base64-encoded, not encrypted. Anyone with the token can read it. Always verify signatures and trust boundaries on the server—never rely on client-side decoding alone.
About JWT debugging
Decode JWT header and payload in your browser for debugging and learning. This tool does not verify signatures and does not send your token to a server.
Why use a JWT debugger?
During API integration you often need to confirm algorithm claims, audience, expiry, and custom fields. Decoding locally lets you inspect structure without pasting tokens into untrusted services.
What this tool does
- Splits a JWT into parts and decodes header and payload JSON.
- Runs entirely in the browser—your token stays on your device.
- Pretty-prints JSON for easier reading and copying.
- Shows clear errors when the format or Base64URL data is invalid.
How to use
- Paste a JWT into the input area.
- Review the decoded header and payload panels.
- Use copy actions if you need the JSON in another tool.
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