← Back to Tools

JWT Decoder

Decode JWT tokens and view header and payload. All processing happens in your browser.

Paste your JWT token
Enter a JWT token (header.payload.signature) to decode and inspect its contents.

What is a JWT Decoder?

A JWT (JSON Web Token) decoder lets you inspect the contents of a JWT without running code. JWTs are used for authentication—they contain a header, payload (claims like user ID, expiration), and signature. Paste a JWT to see the decoded header and payload, check expiration (exp), issued-at (iat), and other claims.

How to Decode a JWT

  1. Paste your JWT token (the long string with dots: xxx.yyy.zzz) into the input box.
  2. Click "Decode". The header and payload appear in readable JSON.
  3. Check exp, iat, nbf for timestamps. Copy the raw payload if needed.

When to Use

Debug auth issues, verify token contents, check expiration before it fails, inspect claims from OAuth/OpenID, or learn how JWTs work. Note: this only decodes—it does not verify the signature. Never paste production secrets. All decoding happens in your browser.