100 Javascript Interview questions to Crack any Interview

100 Javascript interview questions that I prepared for clearing javascript interviews in MS/Walmart/Paytm/Flipkart etc. This set of Javascript interview questions will work for any Software Engineer level Front End interviews.

100 Javascript Interview questions to Crack any Javascript Inteview

1. 1. Data Types in JS
   2. Falsy Values
   3. Map, Reduce, Filter functionalities
   4. Prototypical Inheritance in Javascript
   5. Generator Function (function()*, yield)
   6. Caching based questions (Headers, Expiry, Types etc)
   7.  PWA & TWA ( Caching, Service Workers, Manifest File)
   8. Server Side Rendering
   9. Throttle & Debounce, important concept for Front End developer interview
   10. Iterators in Javascript
   11. Pollyfills for in built functions
   12. Split, Replace, Splice, Slice
   13. Query Selector in Javascript
   14. Substring, Trim and other string operations
   15. Typeof related output questions
   16. HTML5 features
   17. Web worker based Javascript Interview Questions
   18. Scoping in Javascript (this)
   19. Closure
   20. How to Memoize any Javascript Function – Memoization
   21. Hoisting
   22. Design Patterns in Javascript( Modular, Factory, Observer, Pub Sub, Singleton etc)
   23. Currying – add(1)(3)(4)..(n)() and other variations
   24. Call, Apply, Bind based javascript interview questions
   25. Prototype Chain in Javascript
   26. Declaring and extending classes using functions (ES6 to ES5)
   27. Levels of Javascript Scoping
   28. Arrow functions scope
   29. WSS and WS sockets

1. 1. Promises (all, finally etc) based Javascript interview questions
   2. Deep vs Shallow Copy in Javascript
   3. Binary Search based questions
   4. Deleting Object Keys
   5. HasOwnProperty in Javascript Objects
   6. Two way binding implementation
   7. Implicit/Hard/Explicit/New Binding
   8. Callback to Promise conversion
   9. Callback hell
   10. Async/Await over Promise
   11. Eval Function
   12. isExtensible, freeze, sealed and other Javascript Object methods
   13. In built sort() with numbers
   14. Local Storage, Session Storage, Cookie etc(types of storage)
   15. Javascript:void(0)
   16. Event Bubbling, Event Capture, Event Delegation
   17. Difference between var vs let
   18. Output based questions on undefined vs reference error
   19. some, find, includes and other in built Javascript methods
   20. Oninput Event

1. Anonymous function
2. Flatten a nested array in Javascript
3. Private Variable in Javascript
4. Destructing
5. Rest Operators
6. Async vs defer in script tag
7. Fetch() in Javascript
8. Single page application architecture
9. SPA effect on Search Engine Optimization
10. XHR requests
11. Event Loop based Javascript interview questions
12. Message Queue
13. Job Queue
14. Call Stack
15. What is a Tick?
16. Decimal to Hexadecimal conversions
17. Why do we use “use strict”
18. Shift/Unshift in Arrays based Javascript interview questions
19. Escape/Unescape
20. Encode URI
21. Data-ng attributes
22. Dom tree implementation
23. Reactive Programming
24. React based javascript interview questions
25. Virtual DOM Implementation of React
26. Hooks – Usestate, useeffect, useref, useCallback, useMemo
27. Pure Components
28. Higher Order Components
29. Styled Components
30. Context API
31. Redux based javascript interview questions
32. Design Pattern behind redux
33. Shadow DOM
34. Frameworks specific questions based on your resume
35. JS events(onkeyup, onkeydown, onmouseover etc)
36. Finding document width/height
37. Functional programming methodologies
38. Accessing nested objects and listing all key value pairs
39. Load balancers
40. Scaling applications
41. How does CDN works?
42. Implementation of linked lists in JS
43. All ES6 features
44. JSON parse, stringify etc
45. How does webpack works(dependency graph, chunk formation etc)?
46. How does babel works?
47. Node JS based basic javascript interview questions
48. Deprecated react lifecycles and their drawbacks?
49. Optimization of the problems that you are going to solve
50. Frameworks vs VanillaJS
51. Every word you say will be or can be used as a counter question so don’t bring any new topic that you aren’t confident about.

Frontend Interview Questions & Experiences at Amazon, Flipkart, Walmart, MMT, OYO etc

• Frontend Interview Experiences