T

JWT Decoder

Online JWT Decoder

JWT Decoder Description

Decode JSON Web Tokens (JWT) to see header and payload content. Helpful for debugging authentication tokens.

How to use

  1. Paste your encoded JSON Web Token into the input.
  2. The tool will split the token into Header, Payload, and Signature.
  3. The JSON content of the Header and Payload is automatically formatted for reading.

Common Scenarios

  • Debugging authentication issues by checking token expiration (exp).
  • Inspecting user roles or permissions embedded in the token payload.
  • Verifying the algorithm used for signing the token.

Data Structure

A JWT consists of three parts separated by dots (.): Base64Url(Header).Base64Url(Payload).Signature.

Principles

It decodes the first two parts of the token from Base64Url to a JSON string. Note: This tool is for inspection only and does not verify the signature's validity without a secret key.