Express.js is the backbone of many Node.js applications, making it a hot topic in backend and full-stack developer interviews. If you’re prepping for one, knowing the most asked Express.js interview questions and answers can give you a serious advantage.

Common questions include: What is Express.js and how does it differ from Node.js? How does routing work in Express? and What are middleware functions? You may also face practical tasks like building RESTful APIs, handling errors, securing routes, or integrating third-party middleware like body-parser or helmet.

For experienced roles, expect questions about performance tuning, asynchronous behavior, and integrating Express with databases or front-end frameworks.

Mastering these Express.js interview questions and answers will help you confidently navigate technical discussions and stand out in interviews—whether you're aiming for a startup or a big tech company.