JWT Decoder & Encoder Online
Decode JWT tokens, verify RS256 signatures, and generate signed JWT tokens using HS256 or RS256 instantly. Free and secure — runs entirely in your browser.
JWT Decoder & Encoder
Decode JWT tokens or encode JSON to JWT format
Decode JWT
OR
Encode JWT
Fill in the fields below to generate a signed JWT.
HEADER: ALGORITHM & TOKEN TYPE
PAYLOAD: DATA
SIGN JWT: SECRET (HS256)
What is a JWT (JSON Web Token)?
A JSON Web Token (JWT) is a compact, URL-safe token format used to securely transmit information between systems. It consists of three parts separated by dots:
- Header – defines algorithm and token type
- Payload – contains claims (data)
- Signature – verifies authenticity
How to Decode a JWT Token
- Paste your JWT token above.
- Click "Decode JWT".
- View header and payload instantly.
How to Verify RS256 JWT Signature
To verify a JWT signed with RS256, paste the public key in PEM format. The tool validates the signature directly in your browser. No data is sent to any server.
Supported Algorithms
- HS256 (HMAC SHA256)
- RS256 (RSA SHA256)
Is This JWT Tool Secure?
Yes. All decoding and signature verification happens locally in your browser. Puya does not store, log, or transmit JWT tokens.