JsonifyTools

    JWT Decoder

    Decode and inspect JSON Web Tokens

    JWT Token
    0 chars

    Enter a JWT token to decode

    What is a JWT Decoder?

    A JWT Decoder is a developer tool used to decode JSON Web Tokens (JWT) and display their contents in a readable format. It extracts the token’s header, payload, and signature without validating the token.

    What is a JSON Web Token (JWT)?

    A JSON Web Token is a compact, URL-safe token used for authentication and authorization. It is commonly used in APIs, single-page applications, and microservices to securely transmit claims between parties.

    JWT Structure Explained

    • Header: Algorithm and token type
    • Payload: Claims such as user ID and expiration
    • Signature: Used to verify token integrity

    JWT Decode Example

    JWT Token

    eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOjEyMywiZXhwIjoxNzAwMDAwMDAwfQ.abc123signature

    Decoded Payload

    {
  "userId": 123,
  "exp": 1700000000
}

    Common JWT Use Cases

    • Debugging authentication issues
    • Inspecting API access tokens
    • Checking token expiration times
    • Verifying claims during development
    • Learning how JWT authentication works

    Security Notice

    This JWT Decoder does not verify signatures. It should only be used for debugging and development purposes. Never trust decoded data without validating the token on the server.

    Why Use This JWT Decoder?

    • Instant decoding with no backend calls
    • Clear separation of header and payload
    • Automatic expiration detection
    • Safe client-side processing
    • Ideal for frontend and backend developers