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
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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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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.
Discussions

[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
🌐 r/javascript
87
115
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
🌐 r/javascript
44
64
January 23, 2023
JavaScript 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
🌐 r/learnjavascript
19
34
December 11, 2023
Javascript Interview Prep Resources
Thanks for sharing this - looks great! Will be helpful for a lot of people. More on reddit.com
🌐 r/developersIndia
3
6
January 23, 2024
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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.
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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
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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.
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Codecademy
codecademy.com › learn › technical-interview-practice-with-javascript
Technical Interview Practice with JavaScript | Codecademy
Learn what is JavaScript and why it is the most popular programming language. Discover its history, web development role, backend capabilities, and future potential in technology. ... Learn some common interviewing tricks and tips. Then practice some real interview questions in Java.
Find elsewhere
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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.
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DEV Community
dev.to › tomeraitz › tricky-javascript-questions-7nk
Tricky JavaScript Questions - DEV Community
October 7, 2020 - 70 JavaScript Interview Questions - Excellent article that you can learn a lot about JavaScript foundations. What Makes Javascript Weird...and AWESOME - I found this Youtube playlist, In my opinion, the explanations are very understandable, and he shows visual code examples.
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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....
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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.
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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().
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LeetCode
leetcode.com › discuss › interview-question › 4629773 › 30-must-do-Javascript-questions-for-Interviews
30 must do Javascript questions for Interviews - Discuss - LeetCode
The patterns in these questions will prep you end-to-end for Interviews and solidify your core concepts. Implement a function that converts a Javascript value into a JSON string.
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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 ...
Rating: 3.9 ​ - ​ 66 votes
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GitHub
github.com › priya42bagde › JavaScriptCodingInterviewQuestions
GitHub - priya42bagde/JavaScriptCodingInterviewQuestions: JavaScript Coding Interview Questions · GitHub
JavaScript Coding Interview Questions. Contribute to priya42bagde/JavaScriptCodingInterviewQuestions development by creating an account on GitHub.
Starred by 702 users
Forked by 319 users
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Toptal
toptal.com › developers › 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.
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Coderbyte
coderbyte.com › algorithm › 10-common-javascript-interview-questions
10 common JavaScript interview questions
November 24, 2015 - Evaluate candidates quickly, affordably, and accurately for assessments, interviews, and take-home projects. Prepare for interviews on the #1 platform for 1M+ developers that want to level up their careers.