138 interview questions on Javascript for developers (2025)

104 votes4049 runs

47 votes3708 runs4 comments

28 votes3815 runs

13 votes3996 runs

conditionals

Adrienat Mar 30, 2022

11 votes4279 runs0 comment

Kahinaat Apr 12, 2022

11 votes4256 runs

Kahinaat Apr 6, 2022

11 votes4058 runs

spread operator

Kahinaat Jul 19, 2024

11 votes4032 runs2 comments

Kahinaat Apr 6, 2022

10 votes4262 runs

if else conditions

Kahinaat Apr 6, 2022

10 votes4132 runs

10 votes2343 runs3 comments

Jean-marie Cléryat Nov 8, 2023

9 votes2376 runs

Jean-marie Cléryat Jan 4, 2022

8 votes4119 runs

Kahinaat Apr 6, 2022

8 votes2984 runs

Axelat Sep 4, 2023

7 votes4008 runs0 comment

Kahinaat Mar 29, 2022

7 votes2777 runs

Damienat Sep 4, 2023

7 votes2449 runs0 comment

Jean-marie Cléryat Jan 4, 2022

7 votes2401 runs

Jean-marie Cléryat Jan 4, 2022

7 votes2368 runs0 comment

Jean-marie Cléryat Jan 4, 2022

7 votes1591 runs3 comments

Kahinaat Mar 21, 2022

138 interview questions on Javascriptfor developers (2025)

Test your technical skills before an interview of Javascript with 138 corrected questions. Beginner, Intermediate or Expert level.

138 interview questions on Javascriptfor developers (2025)

Test your technical skills before an interview of Javascript with 138 corrected questions. Beginner, Intermediate or Expert level.

Understanding the differences between `map()` and `forEach()` methods in JavaScript

Write a JavaScript function that fetches data from an API and logs it to the console.

Fix the following Javascript loop:

Write a Javascript code that displays 'Adversity is not to be feared' and 'There is potentially a real danger'

What can be said about ECMAScript?

The certificate variable is not attainable outside the if loop

Use spread operator to split an array into two arrays in Javascript

Write a for in loop in Javascript

Write a switch statement that checks if a person can go down a slide based on their weight and height.

Print the number of countries in the array travel.

Write a Javascript code that prints the indexes of an array.

Which of the following equality(s) are true? 0 == '', 'f' + 1 == 'f1'

Filter the elements of an array in Javascript

Find the index of the last element of an array in JavaScript

Add Lyon to the end of the city array

Get the current page URL in Javascript

What will this code display?

Invert a string in Javascript

Which of the following is the **most optimized** method for creating a literal object?

Access the value of the 'level' attribute in a Javascript object

Which of the following is the most optimized method for creating a literal object?