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JWT Decoder Tool
Decode a JSON Web Token.
Paste a JWT to instantly view its header and payload.
Header & Payload
See exactly what's encoded in a JWT's header and payload sections.
Debug Tokens
Useful for debugging authentication tokens and API testing.
Free & Unlimited
No signup, no watermarks, no limits. Use it as many times as you like.
What is the JWT Decoder Tool?
JWT (JSON Web Token) is widely used for authentication in modern web applications. This tool helps you decode JWT tokens to view header and payload information instantly.
Why use this tool?
- Debug authentication tokens
- View encoded data easily
- Understand JWT structure
- Useful for developers and API testing
Frequently Asked Questions
No. This tool only decodes the header and payload sections, which are just Base64-encoded, not encrypted. It does not verify the signature against a secret key.
Treat JWTs like any sensitive credential. For testing with real production tokens, prefer using a local/offline decoder, since a JWT's payload can contain sensitive claims.
Yes. 100% free — no account required, no watermarks, no usage limits.