JWT верификатор
Проверка подписей JWT с помощью алгоритмов HMAC. Вставьте токен, введите секрет и проверьте.
About JWT Verifier
Verifying the authenticity of a JSON Web Token (JWT) is critical for application security. Our free online JWT Verifier allows you to validate token signatures using your secret key or public certificate directly in your browser.
How It Works
The tool takes your JWT and your provided secret key (for HS256) or public key (for RS256). It uses the browser's Web Crypto API to recalculate the signature based on the header and payload, and compares it to the signature attached to the token.
Common Use Cases
- Testing if a JWT was signed with the correct secret key
- Verifying RS256 tokens using a public PEM certificate
- Debugging 'Invalid Signature' errors in authentication flows
- Checking if a token has expired or is not yet valid
Frequently Asked Questions
Yes. The verification process happens entirely locally in your web browser. Your secret key and token are never sent to our servers. However, for production environments, you should always be cautious with live secret keys.
The tool supports the most common JWT signing algorithms, including HS256 (HMAC with SHA-256) and RS256 (RSA Signature with SHA-256).