JavaScript Interview Prep Cheatsheet — Ace Your Coding Interviews

Skylar Johnson
3 min readJul 4, 2023


Introduction: JavaScript (JS) is the one of the most widely used programming languages and knowledge of JS is a valuable skill for developers. When it comes to finding a job in the tech industry, JavaScript interviews can be tough and crucial. In order to stand out from the competition and successfully master JS interviews, a comprehensive preparation strategy is essential. In this article, we’ll look at how to properly prepare for JS interviews so you can demonstrate your expertise and land your dream job.

Read More: How to create programming language that compiles to JavaScript?

  1. Consolidate your JavaScript Basics: Um To pass a JS interview, you need to have a solid understanding of the basics of the language. Start by reviewing basic concepts such as variables, data types, functions, control flow, loops, and objects. Familiarize yourself with ES6 features such as arrow functions, classes, promises, and modules. Understanding these core concepts will help you answer questions effectively and demonstrate your understanding of JavaScript principles.
  2. Key Concepts — To demonstrate your strong knowledge of JavaScript, focus on the main key concepts that come up often in interviews. These concepts can include closures, prototyping, scoping, elevation, event delegation, asynchronous programming, and design patterns. Explore these topics in depth, practice coding exercises, and gain a deep understanding of how they work. The ability to clearly explain these concepts and apply them to real life scenarios will greatly impress your interviewer.
  3. Practice Problem Solving: Problem solving is an essential part of JavaScript interviews. Prepare by solving coding and algorithm challenges using JavaScript. Platforms like LeetCode, HackerRank, and CodeSignal offer a wide range of hands-on tasks to improve your troubleshooting skills. Focus on optimizing your code for efficiency and readability. Also, practice solving common JS interview questions related to array manipulation, string manipulation, recursion, and object-oriented programming.
  4. Understanding DOM manipulation and event handling: JavaScript is commonly used to manipulate web pages and process user interactions. Make sure you have a solid understanding of the Document Object Model (DOM) and of manipulating HTML elements with JavaScript. Practice common DOM manipulation tasks such as dynamically adding and removing elements, modifying styles, and handling events. This knowledge is valuable for front-end development roles and demonstrates your ability to build interactive web applications.
  5. Dive into popular JS frameworks: Many companies use popular JavaScript frameworks such as React, Angular, or Vue.js in their projects. Familiarize yourself with at least one of these frameworks as it will greatly increase your chances of success. Understand the fundamental concepts, architecture, and best practices of your chosen framework. Practice building small projects with the framework and be prepared to share your experiences with him during the interview.
  6. Keep up to date with industry trends: The tech industry is changing rapidly and keeping up with the latest JavaScript trends and advancements is essential. Follow influential JS blogs, subscribe to developer newsletters, and participate in online communities such as GitHub and Stack Overflow. Stay informed about new features introduced in popular JavaScript versions and libraries. Through this continuous learning, you not only broaden your technical knowledge, but also show your passion for the subject in job interviews.
  7. Mock interviews and personal projects: To gain confidence and simulate real-life interview scenarios, consider participating in mock interviews with peers or attending coding boot camps. Mock interviews can help you identify areas where you can improve, sharpen your communication skills, and handle interview pressure effectively. Plus, working on personal projects that showcase your JavaScript skills will give you hands-on experience and a valuable portfolio to present to potential employers.

Conclusion: cracks require JavaScript maintains a combination of deep theoretical knowledge, problem-solving skills, and practical experience. Focus on the basics, master major JavaScript topics, practice troubleshooting, understand DOM manipulation, dive into common frameworks, stay up to date, and participate in tutorials



Skylar Johnson

I'm a Web developer who is always looking to learn more and eat too much chocolate.