How to Set Up JWT Authentication in Spring Boot (Complete Step-by-Step Guide)

Introduction When you start building REST APIs with Spring Boot, one of the first real challenges you face is authentication. How do you make sure that only logged-in users can access certain endpoints? How do you keep the API stateless so that it can scale properly? The answer that most modern backend developers reach for is JWT — JSON Web Token. If you already know Spring Boot but JWT feels like a black box to you — this article is written exactly for you. We are not going to just