ZeroServer.tools

JWT Decoder

Decode JSON Web Tokens instantly. Tokens are never sent to a server.

What is a JSON Web Token (JWT)?

A JWT is a compact, URL-safe means of representing claims to be transferred between two parties. The claims in a JWT are encoded as a JSON object that is used as the payload of a JSON Web Signature structure, enabling the claims to be digitally signed.

Why you should never use server-side JWT decoders

JWTs often contain sensitive user session data or authentication tokens. Pasting them into third-party, server-backed websites is a massive security risk. ZeroServer's JWT Decoder splits and decodes your token's Base64Url header and payload directly within your DOM, keeping your authentication data strictly on your machine.