JWT Decoder

Identify and inspect the contents of your JSON Web Tokens.

JWT Decoder

Decode JWT headers and claims locally. This tool does not verify signatures.

JWT token

Header

{
  "alg": "HS256",
  "typ": "JWT"
}

Payload

{
  "sub": "1234567890",
  "name": "Dev Tools Hub",
  "iat": 1516239022
}

What is JWT Decoder?

A JWT Decoder allows you to see exactly what data is encoded within a token without needing the secret key. It breaks the token into its three constituent parts: the Header (algorithm and type), the Payload (claims and data), and the Signature. Our tool is privacy-focused, performing all decoding locally in your browser.

When to use JWT Decoder?

Debugging authentication issues in web applications

Verifying token expiration (exp) and issued-at (iat) times

Checking custom claims and user permissions within a token

Validating token structure during development

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