JWT Decoder & Token Inspector, private by default

What a JWT decoder shows

A JSON Web Token usually has three dot-separated parts: header, payload, and signature. The header and payload are Base64URL-encoded JSON, which means they can be decoded into readable text.

Decoding helps developers inspect claims during debugging, support reviews, test environments, and documentation work. It is a visibility tool, not a trust decision.

Decoding is not verification

Anyone can edit the payload of an unsigned or incorrectly handled token. A secure application must verify the signature with the correct key, confirm the issuer and audience, enforce expiry and not-before times, and handle revocation or session invalidation.

This tool intentionally does not verify signatures or contact identity providers. It only decodes the readable parts so you can inspect what the token says.

• Check alg and typ in the header
• Review iss, aud, sub, exp, iat, and nbf claims
• Do not rely on decoded claims until a trusted backend verifies them
• Avoid pasting live access tokens into tools that upload data

Private developer workflow

Use local decoding when you need to understand a token shape, debug a test login, or compare expected claims. Redact or avoid real production tokens whenever possible.

If you need proof that a token is valid, use your application backend, identity provider tooling, or a trusted verification library configured with the correct keys and expected claims.