JWT decode workflow — inspect tokens safely

Step-by-step guide to decode and validate JWT header and payload locally without sending tokens to a server.

JSON Web Tokens carry signed claims for APIs and SSO. Before trusting a token, developers decode the header and payload, check exp/iss/aud claims and verify signatures with the right key.

This guide uses Tentaco JWT Decoder in Security Studio — all parsing stays in your browser. Never paste production tokens into untrusted sites.

Steps

Open JWT Decoder from Security Studio or /use/jwt-decoder.
Paste the JWT (three Base64url segments separated by dots).
Review decoded header (alg, typ) and payload claims (sub, exp, iss).
Check exp against current time — reject expired tokens.
Verify signature locally if you have the secret or public key — do not trust claims without verification.

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JWT decoder online — inspect tokens free