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Text & Code Live tool

JWT Decoder

Decode JSON Web Token headers and payloads locally so you can inspect claims without verifying or uploading the token.

Tool Flow

01 Input 02 Process 03 Output

Tool Guide

About the JWT Decoder

Use the JWT Decoder to inspect JSON Web Token headers and payload claims without sending the token to a server. It decodes Base64URL sections, formats the header and payload JSON, and summarizes common claims like issuer, subject, audience, issued-at, not-before, and expiration.

Common uses

  • Inspect JWT claims while debugging authentication flows.
  • Check whether a token looks expired or not yet valid.
  • Read token header metadata such as alg and typ.
  • Copy formatted header or payload JSON into a ticket or local test note.

Browser workflow

  1. 01 Paste a JWT, with or without a Bearer prefix.
  2. 02 Review the claims summary and signature warning.
  3. 03 Copy the formatted header or payload JSON for debugging.