The JavaScript Interview Handbook: 100+ Interview Questions

The ultimate guide to JavaScript interviews. Developed by FAANG engineers, practice with real-world interview questions, gain confidence, and get interview-ready in just a few hours.

Intermediate

151 Lessons

10h

Certificate of Completion

The ultimate guide to JavaScript interviews. Developed by FAANG engineers, practice with real-world interview questions, gain confidence, and get interview-ready in just a few hours.

AI-POWERED

Mock Interview

Explanations

AI-POWERED

Mock Interview

Explanations

This course includes

198 Playgrounds

36 Challenges

61 Quizzes

This course includes

198 Playgrounds

36 Challenges

61 Quizzes

Course Overview

Preparing for coding interviews can be a long, arduous process. Many developers will tell you they spend countless hours grinding through hundreds of coding questions in order to feel confident. This course will help simplify the grind by showing you what topics to spend your time on and what questions you can expect within those topic areas. In this course you will focus on the fundamental concepts of JavaScript that interviewers expect you to know. You’ll practice interview questions related to: JS langu...Show More

Course Content

Introduction

Get familiar with essential JavaScript concepts to ace frontend interviews.

About This Course

Evaluate Yourself

Language Basics

Discover the logic behind JavaScript basics, including hoisting, closures, scope, and array manipulation.

Quiz: Hoisting

Solution Review: Hoisting

Challenge: Create an Amount

Solution Review: Create an Amount

Challenge: Check Parentheses

Solution Review: Check Parentheses

Quiz 1: Arrow Functions

Solution Review: Arrow Functions

Quiz 2: Arrow Functions

Solution Review: Arrow Functions

Challenge: Where to Insert

Solution Review: Where to Insert

Quiz: Call, Apply, Bind

Solution Review: Call, Apply, Bind

Quiz 1: Closure

Solution Review: Closure

JavaScript Execution: Call Stack & Event Loop

Immediately Invoked Function Expressions (IIFE)

Quiz: Closure, `setTimeout`, Scopes

Solution Review: Closure, `setTimeout`, Scopes

Quiz: Closure, `setTimeout`, IIFE

Solution Review: Closure, `setTimeout`, IIFE

Challenge: Create Phone Number

Solution Review: Create Phone Number

Challenge: Insert Elements

Solution Review: Insert Elements

Challenge: Bind Function

Solution Review: Bind Function

Quiz: Rest & Spread Syntax

Solution Review: Rest & Spread Syntax

Challenge: Destructuring

Solution Review: Destructuring

Challenge: Array Destructuring

Solution Review: Array Destructuring

Challenge: Return the Cat

Solution Review: Return the Cat

Challenge: Destructure Undefined

Solution Review: Destructure Undefined

Type coercion

Break apart type coercion concepts using "typeof", "instanceof", prototypes, validation, and inheritance in JavaScript.

Event Handling

Break down complex ideas in JavaScript event handling concepts and their interview applications.

Quiz: Call Stack & Event Loop

Solution Review: Call Stack & Event Loop

Quiz: Event Bubbling

Solution Review: Event Bubbling

Quiz: Event Capturing

Solution Review: Event Capturing

Quiz: Event Delegation

Solution Review: Event Delegation

Asynchronous Callbacks

Map out the steps for understanding and solving asynchronous programming challenges with callbacks, promises, and async/await.

Challenge: Callback Functions

Solution Review: Callback Functions

Challenge: Check the Names

Solution Review: Check the Names

Challenge: Asynchronous Callback Functions

Solution Review: Asynchronous Callback Functions

Quiz 1: Promises

Solution Review: Promises

Challenge: Even or Odd?

Solution Review: Even or Odd?

Quiz 2: Promises

Solution Review: Promises

Challenge: Print Numbers Sequentially

Solution Review: Print Numbers Sequentially

Quiz: Async & Await

Solution Review: Async & Await

Functional Programming

25 Lessons

Master functional programming concepts through practical quizzes, challenges, and in-depth solution reviews.

Security

6 Lessons

Step through key JavaScript security concepts such as same-origin policy, strict mode, and object manipulation protections.

DOM and Web Browser

14 Lessons

Walk through various DOM manipulation techniques and problem-solving challenges with hands-on JavaScript tasks.

Go through your front-end interviews with confidence and land a high-paying job.

Ace the Front-end Interview

Go through your front-end interviews with confidence and land a high-paying job.

5 Modules

Trusted by 1.4 million developers working at companies

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Carlos Matias La Borde

Software Developer

Souvik Kundu

Front-end Developer

Vinay Krishnaiah

Software Developer

Eric Downs

Musician/Entrepeneur

Kenan Eyvazov

DevOps Engineer

Souvik Kundu

Front-end Developer

Eric Downs

Musician/Entrepeneur

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Hands-on Learning Powered by AI

See how Educative uses AI to make your learning more immersive than ever before.

Instant Code Feedback

Evaluate and debug your code with the click of a button. Get real-time feedback on test cases, including time and space complexity of your solutions.

AI-Powered Mock Interviews

Put your skills to the test in a simulated interview setting. Receive personalized feedback based on your performance. Available in Premium & Premium Plus plans.

Adaptive Learning

At various checkpoints throughout Educative courses, you will be prompted to take a quick assessment. Receive a condensed curriculum tailored to your strengths and skill gaps.

Explain with AI

Select any text within any Educative course, and get an instant explanation — without ever leaving your browser.

AI Code Mentor

AI Code Mentor helps you quickly identify errors in your code, learn from your mistakes, and nudge you in the right direction — just like a 1:1 tutor!