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JWT Parser
HeaderPayloadSignature
Header
{
  "alg": "HS256",
  "typ": "JWT"
}
Payload
{
  "sub": "1234567890",
  "name": "Jane Doe",
  "email": "jane@example.com",
  "role": "admin",
  "iat": 1716239022,
  "exp": 1716325422
}
sub1234567890
nameJane Doe
emailjane@example.com
roleadmin
iat17162390222024-05-20T21:03:42.000Z
exp17163254222024-05-21T21:03:42.000Z
Signature
abc123signatureplaceholder

Algorithm: HS256

What is a JSON Web Token (JWT)?

A JSON Web Token is a compact, URL-safe token format defined in RFC 7519. It consists of three Base64URL-encoded parts separated by dots: header.payload.signature. JWTs are widely used for authentication, authorization, and secure information exchange between services.

How it works

The header specifies the signing algorithm (e.g., HS256, RS256, ES256) and token type. The payload contains claims — key-value pairs like sub, iat, exp, and custom data. The signature is computed over the header and payload using a secret or private key, ensuring the token hasn't been tampered with.

How to use this tool

  • Paste a JWT string to instantly decode the header and payload
  • View registered claims like exp, iat, and nbf with human-readable timestamps
  • Check whether the token is expired at a glance
  • Inspect the signing algorithm and key ID (kid) from the header

Common use cases

  • Debugging Authorization: Bearer tokens from API requests
  • Verifying token expiration and claims during development
  • Inspecting OAuth 2.0 and OpenID Connect ID tokens
  • Checking the algorithm and structure of tokens from third-party services