JWT Decoder

Decode JWT tokens to inspect header, payload, and expiry

100% In-BrowserNo Server UploadFree, No Signup

Cryptography

JWT Token

Decoded Result

How to Use

Paste JWT token
Paste the JWT token (header.payload.signature format) into the input area.
Decode
Click "Convert" to decode the header and payload into formatted JSON.
Check expiry
If exp/iat/nbf fields are present, human-readable dates and expiry status are shown.

JWT Decoder Examples

Decode a JWT token

Input

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Output

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

--- Payload ---
{
  "sub": "1234567890",
  "name": "John Doe",
  "iat": 1516239022
}

Header and payload JSON plus timestamp conversion are displayed.

Check an expired token

Input

eyJhbGciOiJIUzI1NiJ9.eyJleHAiOjE2MDAwMDAwMDB9.xxx

Output

--- Payload ---
{
  "exp": 1600000000
}

exp: 2020-09-13T12:26:40.000Z
Status: Expired

The exp date and expiry status are shown.

Features

Display JWT header and payload as formatted JSON
Accurate Base64URL decoding
Convert iat/exp/nbf to human-readable dates with expiry check
Automatic expired/valid status display
Local processing (your input is not sent to servers)
Mobile-friendly responsive design
Dark mode support

FAQ

What is JWT?

JWT (JSON Web Token) is a compact token format for securely transmitting JSON claims. It is widely used for authentication and API authorization. A JWT consists of three Base64URL-encoded parts: header, payload, and signature.

Can it verify signatures?

This tool focuses on decoding headers and payloads. Signature verification requires secret or public keys and is not included due to browser security considerations.

Is my data sent to a server?

No. All decoding happens locally in your browser via JavaScript. Your JWT tokens are never transmitted externally.