Validate a JSON Web Token (JWT) by verifying its cryptographic signature and checking standard claims such as expiration, not-before, issuer, and audience.
This online JWT Validator works entirely on the client side and does not send token data or keys to any server. Use it to confirm token authenticity, detect tampering, and troubleshoot authentication issues.
100% Client-Side Execution. No Data Sent to Server Secure
Validate a JWT by verifying its signature and checking registered claims such as expiration and not-before.
Decode a JSON Web Token to instantly view its header and payload. No secret or private key is required.
Generate a signed JWT using custom headers and claims for testing authentication and authorization flows.
All processing happens locally using the browser’s WebCrypto API. Your tokens and keys are never sent to any server, making this tool safe for debugging production JWTs.
A JSON Web Token (JWT) is a compact, URL-safe means of representing claims to be transferred between two parties. It consists of three parts: Header, Payload (claims), and Signature.
JWTs are widely used for API authentication, single sign-on (SSO), and securely transmitting information between client and server. Learn more at JWT.io and Auth0's JWT guide. You can also follow this tutorial to implement the JWT based auth mechanism in spring boot.
JWT validation is the process of verifying that a token has not been tampered with and that it satisfies expected claims. This involves checking the cryptographic signature and validating time-based and issuer-based claims.
Unlike decoding, validation ensures that a JWT is trustworthy and was issued by a known authority.
JWT signatures are generated using symmetric or asymmetric cryptographic algorithms. Validation recomputes the signature using a secret or public key and compares it with the signature embedded in the token.
You can inspect token contents first using a JWT decoder before performing full validation.
JWT validation is secure when keys are handled correctly and tokens are validated in a trusted environment. This tool performs validation entirely in the browser without transmitting token data.
For key-based verification, cryptographic tools such as RSA or ECC are commonly used.
A JWT validator verifies a token’s signature and validates its claims to ensure the token is authentic and has not expired or been altered.
Decoding only reveals token contents, while validation confirms the token’s integrity and authenticity.
Yes. Validation requires either a shared secret or a public key depending on the signing algorithm used.
Yes. This tool validates JWTs entirely in the browser without sending data to a server.
A JWT Validator is used to ensure that a token is authentic, untampered, and valid according to its claims.
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