Introduction

JWT Decoder Online is a free tool that lets you decode and inspect JSON Web Tokens (JWT) entirely in your browser. Paste your JWT to instantly view the header, payload, and signature without sending any data to a server.

How to use:

1. Paste your JWT token in the text box below.

2. Click "Decode" to view the header and payload.

3. The decoded sections are displayed as formatted JSON below.

JWT Token:

Header:

Payload:

Signature:

About JWT Decoder Online:

JSON Web Tokens (JWT) are a compact, URL-safe means of representing claims to be transferred between two parties. They are widely used for authentication and authorization in modern web applications, especially with OAuth 2.0 and OpenID Connect.

A JWT consists of three parts separated by dots: a Header (algorithm and token type), a Payload (claims such as user ID, expiration time, and custom data), and a Signature (used to verify the token has not been tampered with).

This tool decodes the Header and Payload by Base64url-decoding them and formatting the resulting JSON. Note that this tool does NOT verify the signature -- it is intended for inspection and debugging only. All processing happens entirely in your browser; your token is never sent to any server.