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JWT Decoder

Paste a JWT below to decode, validate, and verify locally in your browser.

Demo algorithm
>_ JSON Web Token (JWT)

JWT must not be empty.

Paste or generate a JWT to see decoded header and payload.

JWT signature verification (optional)

 

Verification uses the Web Crypto API in your browser only. Secrets and PEM keys are never uploaded.

About this tool

Decode and inspect JSON Web Tokens: view the header, payload claims, and expiration date. Runs entirely in your browser.

Privacy and details

Your files never leave your device.

Fast browser processing with no account required.

Optimized for desktop and mobile with accessible controls.

How to use
  1. Paste a JWT (three dot-separated Base64URL parts) into the input field.
  2. The header, payload, and signature sections decode automatically.
  3. Check the expiration status: the tool shows if the token has expired.
  4. Copy the decoded payload for use in your code or debugging.
Why use this tool

Debugging authentication issues requires quickly inspecting what a JWT actually contains. This tool decodes any JWT instantly without sending it to a server, making it safe to use with tokens from staging environments.