JWT Token Decoder & Generator - Online JWT Parser and Validator
Decode JWT, verify JWT signature, generate JWT tokens, and inspect JWT payloads with our free online JWT tool
JWT Operation
Result
What is JWT? JWT Generation, Validation, and Parsing Explained
1. What is JWT?
JWT (JSON Web Token) is a compact, URL-safe means of representing claims to be transferred between two parties. It is commonly used for jwt authentication, information exchange, and API authorization. A JWT token consists of three parts: Header, Payload, and Signature, separated by dots.
2. How JWT Works
JWT Generation
To create a JWT, the server encodes the Header and Payload using Base64Url, then signs them with a secret key and algorithm (such as HS256). The final token is the combination of these three parts.
JWT Parsing / Decoding
JWT decode is the process of Base64Url decoding the Header and Payload to view their contents. Our jwt decoder allows you to inspect the token structure and payload data.
JWT Validation
JWT verification ensures the token hasn't been tampered with. The server recalculates the signature using the secret key and compares it with the signature in the token.
3. Why Everyone is Using JWT
- Stateless authentication – no server-side session storage
- Works well with REST APIs and microservices
- Supports single sign-on (SSO)
- Easy to pass between services and domains
- Compact and self-contained
4. Pros and Cons of JWT
Advantages
- Stateless and scalable
- Fast to verify
- Supports cross-domain authentication
- Can carry user claims and metadata
Disadvantages
- Payload is encoded, not encrypted – sensitive data should not be stored
- Tokens can't be revoked easily
- Long tokens may increase bandwidth usage
5. How to Use This Tool
- Use the JWT Decode tab to parse and inspect any JWT token
- Use the JWT Verify tab to check if a token is valid with a secret key
- Use the JWT Generate tab to create a new JWT with custom payload and algorithm
- Copy results with one click