JWT Decoder

Decode and inspect JSON Web Tokens (JWT) instantly. Paste any JWT to see the decoded header, payload, signature status, standard claim explanations, expiration risk, issuer/audience checks, and a copyable claim audit handoff that avoids raw token values.

Runs in your browser Nothing uploaded Free, no signup

Everything stays in this browser

JWT Decoder: questions

Is it safe to paste my JWT here?
Decoding and the claim audit happen 100% in your browser — your token never leaves your machine. Treat JWTs like passwords and avoid pasting production tokens in shared environments.
Can this verify the signature?
No — verifying requires the secret key or public key. This tool decodes the Base64URL-encoded header and payload, flags risky claim patterns, and creates a verification checklist for your backend or CI review.

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