JWT Decoder / Debugger Online

JWTs are everywhere in auth and API access. Debugging APIs or analyzing traffic often means decoding an eyJ… token to read its claims.

Unlike many online tools, this decoder runs entirely in your browser — a JWT usually carries identity and permissions, which should never be uploaded to a third-party server. It decodes only (no signature verification) and formats iat / exp / nbf into readable times, flagging whether it's expired.

Decoded locally (signature not verified) — JWTs carry sensitive credentials; this tool never uploads them.

Check your own IP — purity, risk score, native vs datacenter, leaksCheck IP →

FAQ

Does this JWT decoder upload my token?

No. Decoding happens entirely in your browser; the token never leaves your device — the key difference from some online tools.

Does it verify the signature?

No. It only decodes the Header / Payload for inspection; verifying the signature needs the secret and should happen in your own backend.

How do I check if a JWT is expired?

After decoding, the exp claim is shown as a readable time and flagged valid / expired.

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