I've also struggled with these tech interviews, but I finally managed to memorise tons of questions they like to ask on tech interviews after playing with JS Interview Hell - https://www.javascript-interview-hell.com/ . Answer from niecnasowa on reddit.com
Roadmap
roadmap.sh › questions › javascript-coding
Top 80 JavaScript Coding Interview Questions and Answers
Master your next interview with these top 80 JavaScript coding interview questions and answers, great for all experience levels.
Reddit
reddit.com › r/javascript › [askjs] what are the interview questions you have faced as a javascript developer?
r/javascript on Reddit: [AskJS] What are the interview questions you have faced as a JavaScript developer?
October 2, 2024 -
I have an interview tomorrow basically, I come from a CMS background with Drupal and Front end. I just want to make sure I am aware of most of the answers to the common questions
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I've also struggled with these tech interviews, but I finally managed to memorise tons of questions they like to ask on tech interviews after playing with JS Interview Hell - https://www.javascript-interview-hell.com/ .
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Depends on the role. Make sure you understand the event loop, critical rendering path, types of data, primitives, objects, data structures, closures, scopes, array operations For example, check if a string is a palindrome + complexity. Then you should also check frameworks. You should read https://www.frontendinterviewhandbook.com/ Good luck!
GitHub - lydiahallie/javascript-questions: A long list of (advanced) JavaScript questions, and their explanations Updated weekly! Jun 19, 2019
r/javascript 7y ago
[AskJS] Technical test questions about javascript and related framework Nov 27, 2023
r/javascript 2y ago
What Javascript, React or Typescript questions would you expect a developer to know based on their experience? Jun 22, 2023
r/webdev 3y ago
[AskJS] What are the most common interview questions for frontend?
I think that a deeply understanding of callback, promises, and asynchronous things are top questions atm More on reddit.com
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January 21, 2022[AskJS] What would you study for a entry level JS interview?
All our js is front ends for APIs, so I’d definitely ask about promises, familiarity with REST APIs (how to call them, handle responses). I usually ask a few more basic questions about truthiness and things like double equals vs triple equals. More general web stuff/software dev stuff would be things like responsive design, css/sass, git, agile, unit testing, etc. Personally I wouldn’t care much if you know how to do DOM manipulation if we’re using React, but everyone is different. One piece of advice is don’t try to BS any answers. If you don’t know, be straightforward and ask them about it. Showing interest to learn should be a large part of what they are looking for, and there’s nothing worse than being called out on your own BS. More on reddit.com
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January 23, 2023JavaScript Interview Q&A - Most common JS concepts you should know by heart
I wouldn't care if a candidate doesn't know about hoisting, debouncing and throttling. I don't see these as core JS concepts. Well, I take that back, hoisting obviously is. But I've been doing JS development since '97 professionally and I can't honestly think of a single instance where I had to know anything about hoisting. Maybe that's simply because I've always written code in a logical way, hence hoisting doesn't tend to be a factor. Debouncing and throttling are ideas you can easily learn if and when the need arise, not something you have to know cold in my opinion. The rest are reasonable to test for, though I personally wouldn't consider someone that didn't know some of them disqualified immediately. It would just be one factor among many to consider. More on reddit.com
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December 11, 2023Javascript Interview Prep Resources
Thanks for sharing this - looks great! Will be helpful for a lot of people. More on reddit.com
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January 23, 202401:15:12
50 JavaScript Interview Questions Solved in 1 Hour - YouTube
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Most Common Javascript Interview Questions (I've been asked) - YouTube
InterviewBit
interviewbit.com › javascript-interview-questions
60+ Most Important JavaScript Interview Questions and Answers (2026)
Explore 100+ JavaScript interview questions and answers for 2026, covering basics to advanced topics like closures, hoisting, promises, DOM, and ES6.
Published March 23, 2026
GreatFrontEnd
greatfrontend.com › blog › 10-must-know-javascript-coding-interview-questions
10+ Must-know JavaScript Coding Interview Questions | Blog
March 28, 2025 - These 18 questions cover what front-end interviewers ask in JavaScript coding rounds, from junior screens to senior onsites.
GeeksforGeeks
geeksforgeeks.org › javascript › javascript-coding-questions-and-answers
JavaScript Coding Questions and Answers - GeeksforGeeks
August 5, 2025 - These Top 50 coding questions and answers will help you to improve your coding concept in JavaScript. If you're a beginner and want to gather some real-time coding examples, then start here. This section will help you understand the fundamentals and solve simple coding problems. This code splits the string into an array of characters using the split() method, reverses the array, and joins it back into a string using the join() method.
Medium
medium.com › deno-the-complete-reference › 10-javascript-coding-interview-questions-part-1-a0e5bb606eaf
10 JavaScript coding interview questions — Part 1 | Tech Tonic
August 21, 2025 - The book contains 100 frequently asked JavaScript interview questions with answers.
GreatFrontEnd
greatfrontend.com › blog › 50-must-know-javascript-interview-questions-by-ex-interviewers
50+ Must-know JavaScript Interview Questions by Ex-interviewers (2026) | Blog
May 20, 2026 - 50+ JavaScript interview questions for 2026, with code examples and answers curated by ex-FAANG interviewers. Covers ES2025: immutable array methods, new Set methods (union/intersection), structuredClone, and modern async patterns.
Front End Interview Handbook
frontendinterviewhandbook.com › javascript coding
JavaScript Interview Questions (Machine Coding) for Front End Interviews | The Official Front End Interview Handbook 2026
May 28, 2026 - Almost all existing utility functions you will be asked exist within the JavaScript language or famous third-party libraries like Lodash/Underscore, with the most famous being debounce and throttle. However, Lodash's implementation is extremely over-engineered — reusing a lot of abstract functions and supporting weird and obscure use cases for older browsers; you're not expected to handle such edge cases within an interview setting.
Keka
keka.com › hr toolkit › interview questions › top 50 javascript coding interview questions and answers
JavaScript Coding Interview Questions and Answers List | Keka
Interviewers are looking for candidates who can not only clearly explain the solution along with the code, but also show the ability to think logically and articulate their thought processes. By using the filter method on the array, I can check if each element is even or not by using the modulus operator (%) with 2. The element is even if the result is 0. This can be included in the new array. ... By asking this question, managers aim to assess the candidate’s algorithmic thinking and understanding of JavaScript programming. The interviewer expects the candidate to demonstrate their knowledge of the factorial concept.
GitHub
github.com › sudheerj › javascript-interview-questions
GitHub - sudheerj/javascript-interview-questions: List of 1000 JavaScript Interview Questions · GitHub
List of 1000 JavaScript Interview Questions. Contribute to sudheerj/javascript-interview-questions development by creating an account on GitHub.
Author sudheerj
CodeSignal
codesignal.com › home › blog › interview prep › 25 javascript interview questions (and answers) from basic to senior level
25 JavaScript interview questions (and answers) from basic to senior level | CodeSignal
September 10, 2024 - Front-End Engineering with React ... that front-end JS devs need. Question: Write a JavaScript function createCounter that returns an object with two methods: increment and getValue....
FullStack.Cafe
fullstack.cafe › home › blog › 25+ javascript coding interview questions (solved with code)
25+ JavaScript Coding Interview Questions (SOLVED with CODE) | FullStack.Cafe
November 10, 2019 - Check 👉 179 JavaScript Interview Questions ... The question is when a non-boolean value is coerced to a boolean, does it become true or false, respectively? The specific list of "falsy" values in JavaScript is as follows: ... Above code would give output 1undefined.
Indeed
indeed.com › career-advice › interviewing › javascript-coding-interview-questions
36 JavaScript Coding Interview Questions (With Answers) | Indeed.com
How has learning to code in JavaScript improved your career as a developer? ... Tell me about a time a client changed specifications on a project while you were working on it and how you responded.
CodeInterview
codeinterview.io › home › 30 javascript coding interview questions for developers
30 JavaScript Coding Interview Questions for Developers
September 2, 2024 - When preparing JavaScript coding interview questions for beginner-level JavaScript developers, focus on basic JavaScript IDE, syntax, array and string manipulation, objects and JSON, DOM manipulation, error handling and asynchronous programming. Here are 10 sample questions in this regard: ... const array = [10, 20, 30, 40]; const result = array.map((num) => num / 2).filter((num) => num >= 15); console.log(result); Find the issue in the below code snippet.
Built In
builtin.com › software-engineering-perspectives › javascript-interview-questions
55 Top JavaScript Interview Questions with Example Answers | Built In
JavaScript code for cloning an object using object.assign() and ... operators. | Image: Akshay Kumar · More on JavaScriptJavaScript Question Mark (?) Operator Explained
GreatFrontEnd
greatfrontend.com › front-end-interview-playbook › javascript
JavaScript Coding Interview Questions | How to prepare
November 1, 2022 - Ultimate guide to prepare for JavaScript Coding Interview Questions - including question types, interview best practices, important concepts and practice questions
Toptal
toptal.com › javascript › interview-questions
Top 37 Technical JavaScript Interview Questions & Answers [2026] | Toptal®
OK, fine. But if 3 is being logged after a delay of 0 msecs, doesn’t that mean that it is being logged right away? And, if so, shouldn’t it be logged before 4, since 4 is being logged by a later line of code? The answer has to do with properly understanding JavaScript events and timing.
Udemy
udemy.com › development
100+ JavaScript Coding Practice Test Questions Answers 2026
January 5, 2026 - JavaScript Interview Coding Questions and Answers (Solution Code with Detailed Explanations) Are you preparing for a JavaScript coding interview and seeking to achieve a level of mastery that allows you to confidently address challenging, nuanced questions? This course is meticulously crafted ...
Codinginterview
codinginterview.com › home › javascript coding interview questions and answers
JavaScript Coding Interview Questions and Answers
January 8, 2026 - Modern interviews often include ES6+ questions. They test whether you can use the features that make JavaScript cleaner and more powerful. ... “Template literals let you embed variables and expressions inside backticks, making string handling easier.” · Makes it easier to unpack values from arrays and objects. Spread expands, rest gathers. Encourages modular code.
DEV Community
dev.to › greatfrontend › top-10-expert-crafted-javascript-coding-interview-questions-4gge
Top 10 Expert-Crafted JavaScript Coding Interview Questions - DEV Community
January 16, 2025 - The reduce() method is a staple of functional programming in JavaScript and frequently comes up in front-end interviews. It tests a candidate's ability to: Work with functional-style APIs. Understand array iteration and transformation techniques. Manage accumulator state effectively across iterations. Companies often include questions about reduce() alongside methods, such as map(), filter, and concat().