JWT Decoder
Inspect JSON Web Tokens (JWT) client-side. View decoded header algorithms, payload claims, and convert expiration (`exp`), issued-at (`iat`), and not-before (`nbf`) epoch timestamps to human dates.
How it works
- Paste your encoded JSON Web Token (e.g. `eyJhbGciOi...`).
- The token is split into Header, Payload, and Signature components.
- Base64URL segments are decoded and formatted as structured JSON with readable timestamp labels.
Privacy & Processing Information
Decoded only — signature not verified. Your JWT never leaves your browser, protecting sensitive bearer tokens.
Frequently Asked Questions
Does decoding a JWT verify its cryptographic signature?
No. Decoding only reads the Base64URL-encoded JSON payload. Verifying the signature requires the signing secret or public key on the authentication server.
Is it safe to paste production tokens here?
Yes, this tool runs 100% in your browser and never sends tokens to any backend server.
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