JWT Decoder
Decode JSON Web Tokens (JWT) to inspect their header and payload without a backend.
What is this tool?
A JWT Decoder reads the Base64-encoded header and payload of a JSON Web Token so you can inspect the claims without needing the secret key.
How does it work?
The tool splits the token on dots, Base64-decodes the first two parts, and pretty-prints the JSON.
How to use JWT Decoder
- Paste your JWT token.
- Inspect the decoded Header and Payload sections.
Common Use Cases
- Debugging authentication issues
- Inspecting API tokens
- Verifying token claims during development
Frequently Asked Questions
Is it safe to paste my JWT here?
Yes. Decoding is done entirely in your browser — the token is never sent to any server.
Does it verify the signature?
No. This tool only decodes (reads) the header and payload. Signature verification requires the secret key.