JWT Debugger

Summary

Decode, verify, and edit all three JWT sections with live validation feedback.

How it works

1. Paste a JWT
2. Edit header or payload JSON directly
3. Provide the secret or public key
4. See signature valid or invalid in real time

Use cases

• Diagnosing invalid-signature errors in production
• Experimenting with JWT claim modifications
• Teaching JWT structure interactively

Frequently Asked Questions