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JWT Decoder— Free & Private

Decode and inspect JSON Web Tokens — header, payload, and signature — in your browser.

Processed in your browser. Nothing uploaded.

What Is JWT Decoding?

JWT (JSON Web Token) decoding parses the three Base64-encoded sections of a JWT — the header, payload, and signature — into readable JSON. JWTs are widely used in authentication and authorization flows across modern web applications. Our decoder lets you inspect token claims, expiration times, and signing algorithms directly in your browser without sending sensitive tokens to any external service.

How to Use JWT Decoder

  1. Paste your JWT

    Copy your JSON Web Token and paste it into the input field.

  2. View decoded sections

    Instantly see the header, payload, and signature decoded into readable JSON.

  3. Inspect claims and expiry

    Review token claims such as issuer, subject, expiration time, and custom data.

Why Use Our JWT Decoder?

Decodes header, payload, and signature sections instantly
Runs entirely in your browser — tokens never leave your device
Highlights expiration dates and validates token structure
Supports all standard JWT signing algorithms (HS256, RS256, ES256, etc.)
Color-coded display for easy reading of claims
No account or API key required
Ideal for debugging OAuth, API authentication, and SSO flows

Frequently Asked Questions

Does this tool verify the JWT signature?

The tool decodes and displays all three sections of the JWT. Signature verification requires the secret key or public key, which you can optionally provide to validate the token.

Is it safe to paste my JWT into an online tool?

With our decoder, yes. The entire decoding process happens in your browser. The token is never transmitted to any server or stored anywhere. For production tokens, always prefer client-side tools like this one.

What information can I see in a decoded JWT?

The header reveals the signing algorithm and token type. The payload contains claims such as the issuer (iss), subject (sub), expiration time (exp), issued-at time (iat), and any custom claims added by the application.