JWT Decoder & Inspector
Inspect, decode, and pretty-print JSON Web Token headers, claims, expiration dates, and payloads.
How to Use JWT Decoder & Inspector
Paste your Bearer token or raw JWT (header.payload.signature).
Read decoded JSON Header and Payload blocks.
Check expiration validity and claims.
JWT Decoder & Inspector runs 100% client-side in your web browser. Your data, passwords, keys, and files are processed using the Web Crypto API and never transmitted to any server. Zero telemetry, zero storage, zero cloud processing.
Frequently Asked Questions
Does decoding a JWT require the secret key?
No! The header and payload are Base64URL-encoded JSON and can be read by anyone. The secret is only needed to verify the signature.
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