Enter your JWT token below:


Decoded Output:

ℹ️ What is a JSON Web Token (JWT)?

A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties. JWTs are widely used in:

  • OAuth 2.0 & OpenID Connect (OIDC): ID tokens and access tokens
  • API Authentication: Stateless authentication for REST APIs
  • Single Sign-On (SSO): Session tokens across multiple applications
  • Microservices: Service-to-service authentication

JWT Structure (3 parts separated by dots):

  1. Header: Algorithm (HS256, RS256) and token type (JWT)
  2. Payload: Claims (data) like user ID, expiration time, issuer
  3. Signature: Cryptographic signature to verify token integrity

Common JWT Claims:

  • exp (Expiration Time): When the token expires (Unix timestamp)
  • iat (Issued At): When the token was created
  • nbf (Not Before): Token is not valid before this time
  • iss (Issuer): Who created the token (e.g., auth server URL)
  • aud (Audience): Who the token is intended for
  • sub (Subject): User identifier (e.g., user ID)
🔒 Privacy & Security Notice

Client-side decoding only: This JWT decoder runs 100% in your browser using JavaScript. No JWT tokens are transmitted to any server. Your tokens remain completely private.

⚠️ Note: This tool only decodes JWTs (Base64 decoding). It does not verify signatures. Always validate JWT signatures on your backend server before trusting the token data.