JWT: Definition and Use Cases
JWT (JSON Web Token) is a compact cryptographic token consisting of three base64 parts separated by dots: header.payload.signature. It contains claims (user_id, roles, exp) signed with HMAC or RSA. Used for stateless authentication in APIs. Any client can read it without contacting the server, but only a secret can verify it.
What is JWT
JWT (JSON Web Token) is a compact cryptographic token consisting of three base64 parts separated by dots: header.payload.signature. It contains claims (user_id, roles, exp) signed with HMAC or RSA. Used for stateless authentication in APIs. Any client can read it without contacting the server, but only a secret can verify it.
Check JWT online
Understanding the Structure of JWT
JWT Authentication Flow: A Step-by-Step Guide
Practical Example: Implementing JWT in a Node.js Application
Learn more
Glossary
Frequently Asked Questions
Do I need JWT?
If you work with web infrastructure or APIs, almost certainly yes. See the article above for specific use cases.
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