Top 75 Frontend Javascript Interview Questions

If you have been trying to prepare for front-end engineering interviews, and are struggling to find what are the most commonly asked questions, you are not alone. Here are the top 75 JavaScript interview questions to practice, with MDN’s JavaScript reference for deeper reading.

We know the struggle; which is why we aggregated the most frequently asked Frontend Javascript interview questions, sourcing them from various places, such as Glassdoor, Blind, and others to identify the most commonly asked questions in front-end interviews conducted by companies like Meta, Google, Apple, Robinhood, and more.

In this article, we will showcase the 75 most commonly asked Frontend interview questions in JavaScript. This article does not violate any NDA agreements with any company, as all the questions can be found online on websites such as Glassdoor, etc. These questions are less focused on algorithms (non-LeetCode-style questions) and instead, place more emphasis on domain-specific knowledge.

We want to highlight something very important — a significant mistake you can avoid. Understanding the question accounts for 50% of the struggle while knowing the correct solution makes up the other 50%. Prior to diving deep into studying these questions, you might think “I think I know the solutions”. However, there are many ways to solve the same question, and top companies are looking for the most optimized approach, particularly in relation to front-end development.

This is why we created frontendlead.com, a platform that explains every question with a detailed solution alongside a video explanation.

Top 75 Frontend Javascript Questions

• 1. Find Corresponding Node
• 2. Improve a function
• 3. Flatten I
• 4. Debounce I
• 5. Throttle
• 6. Total Salaries
• 7. Gym Sessions
• 8. Array Methods
• 9. Build Promise
• 10. ClassNames
• 11. Create DOM
• 12. Phone Number Parser
• 13.Deep Clone
• 14. Event Emitter
• 15. EventTarget
• 16. Traverse DOM
• 17. Flatten II
• 18. Intersection Observer
• 19. Memoize I
• 20. Masonry Grid
• 21. Navigation
• 22. Next Right Sibling
• 23. Node Store
• 24. Parser for Rich Text Editor
• 25. Promisify Any Function
• 26. Skill Endorsements
• 27. Testing Framework
• 28. Text Highlighter
• 29. Throttle II
• 30. Tic Tac Toe
• 31. Top K Words
• 32. Image Slider
• 33. Virtual DOM I
• 34. Virtual DOM II
• 35. Virtual DOM III
• 36. API Confirmation
• 37. API Search and Render Image
• 38. Asynchronous Request Queue
• 39. Auto Suggest Search List
• 40. Autocomplete Search List
• 41. ClearAllIntervals()
• 42. ClearAllTimeouts()
• 43. Compose Function
• 44. Curry Function
• 45. Custom “this” Methods
• 46. Debounce II
• 47. Debounce III
• 48. Deep Equals
• 49. Event Emitter II
• 50. Event Logger I
• 51. Event Logger II
• 52. File Navigation
• 53. Filtering Matching JSON
• 54. Flatten III
• 55. Flatten IV
• 56. Flatten V
• 57. Flatten VI
• 58. Flatten VII
• 59. Flatten XI
• 60. getElementsByClassName
• 61. Hierarchical Checkbox
• 62. Histogram
• 63. Infinite Scrolling News Feed
• 64. K MostText Nodes
• 65. Memoize II
• 66. Promise Methods
• 67. querySelectorAll
• 68. Rate Limiter
• 69. Animate Element To The Right
• 70. RxJS Observable
• 71. Set Interval with Linear Delay
• 72. Stream
• 73. String Repeater
• 74. Tabs
• 75. Todo App

In conclusion, navigating the landscape of front-end engineering interviews can be a daunting task, especially when it comes to knowing what to expect and how to prepare. This article aimed to demystify the process by bringing together the 75 most frequently asked Frontend JavaScript interview questions sourced from a variety of reliable platforms and industry leaders. Our focus was to move beyond the algorithm-heavy questions typical of many coding interviews and instead, zero in on questions that test a candidate’s practical, domain-specific knowledge.

Remember, understanding the question is just as crucial as knowing the... premium content.