Skip to main content
CheckTown

JWT Validator

Validate JWT structure, decode header and payload, verify the signing algorithm, and check token expiration.

Enter a JWT token above to validate

We'll check structure, decode header and payload, verify algorithm and expiration

What we check

Structure Check

Validating three-part dot-separated JWT structure

Header Decode

Decoding and parsing the Base64URL-encoded header

Payload Decode

Decoding and parsing the Base64URL-encoded payload

Algorithm Verification

Verifying the signing algorithm is recognized

Expiration Check

Checking token expiration (exp) claim

Learn More

JWT Validator: Check JSON Web Token Structure and Claims

Learn how JWT validation works, the header.payload.signature structure, and security best practices.

What Is a JWT?

A JWT (JSON Web Token) is a compact, URL-safe token format used to securely transmit information between parties as a JSON object. Defined by RFC 7519, JWTs are the de facto standard for authentication and authorization in modern web applications and APIs.

5 min readRead full guide