When you’re working with any website, application, or API, you'll inevitably need to log in and authenticate your user base. One of the more commonly used methods of passing around authentication credentials from one system to another is using a JSON...

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JSON Web Tokens (JWT) are digitally signed, self-contained tokens used for secure authentication between systems. JWTs consist of three parts: header (metadata), payload (claims/data), and signature (verification). They can be signed using symmetric algorithms like HS256 with shared secrets or asymmetric algorithms like RS256 with public/private key pairs. The signature ensures authenticity and integrity without requiring server-side session storage. Key security practices include using HTTPS, keeping tokens short-lived, implementing refresh tokens, protecting signing keys, and never storing sensitive data in the payload.

What Are JSON Web Tokens (JWT)?

Symmetric Signing: HS256 (HMAC With SHA-256)

JWTs in Action: A Typical Authentication Flow

JWT Security Best Practices and Considerations