JWT Token Decoder

Decode and inspect JSON Web Tokens (JWT). Enter your JWT token to see the header and payload information.

JWT Token Generator

Header

Payload

Signature

Token Analysis

Token Health
Expired
Token Age
Expiration Date
Algorithm
Security Level
Security Recommendation

Understanding JWT Tokens

What is a JWT Token?

JWT (JSON Web Token) is an open standard for securely transmitting information between parties as a JSON object. These tokens can be verified and trusted because they are digitally signed. JWTs can be signed using a secret or a public/private key pair.

Structure of a JWT Token

  • Header: Contains token type and signing algorithm
  • Payload: Contains the claims or token data
  • Signature: Ensures token hasn't been altered

Common Uses of JWT

  • Authentication and authorization
  • Information exchange
  • Session management
  • API security

Benefits of Using JWT

  • Compact and self-contained
  • Easy to transmit across networks
  • Can contain user information and privileges
  • Supported by multiple programming languages

Security Considerations

  • Never store sensitive information in JWT payload
  • Use HTTPS for token transmission
  • Implement proper token expiration
  • Validate tokens on the server side

Frequently Asked Questions

Are JWT tokens encrypted?

JWT tokens are encoded and signed, but not encrypted by default. The information can be decoded but not modified without the secret key.

How long should a JWT token be valid?

The validity period depends on your security requirements. Access tokens typically last 15 minutes to a few hours, while refresh tokens can last longer.

Can I store JWT tokens in localStorage?

While possible, it's recommended to store tokens in httpOnly cookies to prevent XSS attacks. Consider your security requirements when choosing storage methods.