21 interview questions for developers (2026)

Medium

5 votes195 runs2 comments

Find all the strings that match the regular expression: `/abracadabra{2,4}/gmi`

Back-end developer

RegEx

pattern

Anonymous authorat Mar 28, 2023

Easy

4 votes218 runs0 comment

Which of the following is not a regular expression?

Back-end developer

RegEx

characters

Anonymous authorat Mar 28, 2023

Expert

3 votes168 runs1 comment

Write a regular expression to extract a file name from a path, except if the file is a .html file

Back-end developer

RegEx

file

Anonymous authorat Mar 28, 2023

Medium

2 votes200 runs0 comment

Write a RegEx that has the same behavior as trim (JS) or strip(Python)

Back-end developer

RegEx

functions

Anonymous authorat Mar 28, 2023

Easy

2 votes198 runs0 comment

Write a regular expression that matches a character that repeats exactly 6 times.

Back-end developer

RegEx

character

Nick LAM YEE MANat May 16, 2023

Medium

2 votes193 runs0 comment

Write a regular expression that matches anything that looks like an HTML tag.

Back-end developer

RegEx

html

Anonymous authorat Mar 28, 2023

Medium

2 votes176 runs0 comment

Write a RegEx that will only find the word 'test' in the sentence 'I write a testimonial about this test'

Back-end developer

RegEx

pattern

Anonymous authorat Mar 28, 2023

Easy

2 votes173 runs0 comment

Find the intruder in the following regex: `^[a-zA-Z0-9_-]+$`

Back-end developer

RegEx

pattern

Anonymous authorat Mar 28, 2023

Medium

1 vote196 runs0 comment

Write a regular expression that matches any number in a string

Back-end developer

RegEx

pattern

Anonymous authorat Mar 28, 2023

Medium

1 vote185 runs0 comment

Write a regular expression to match the characters . and ?

Back-end developer

RegEx

characters

Anonymous authorat Mar 28, 2023

Medium

1 vote180 runs0 comment

Write a regular expression that replaces all tags without content with self-closing tags

Back-end developer

RegEx

Find all the occurrences of the substring 'abracadabra' in the string 'abracadabraabracadabraabracadabra'

Back-end developer

RegEx

quantifiers

Anonymous authorat Mar 28, 2023

Medium

1 vote173 runs0 comment

Write a regular expression that matches a valid email address

Back-end developer

RegEx

email

Anonymous authorat Mar 28, 2023

Medium

1 vote168 runs0 comment

What does this RegEx do : `/(^\w+)(?=\.\w+)/old_$1/gm`

Back-end developer

RegEx

file

Anonymous authorat Mar 28, 2023

Easy

1 vote162 runs0 comment

What does the RegEx `/[abc]/` match

Back-end developer

RegEx

regular expressions

character classes

Anonymous authorat Mar 28, 2023

Medium

1 vote143 runs

1 comment

Which RegEx(s) can be used to verify that a password meets these criteria: - at least 1 (one) lowercase letter - at least 1 (one) uppercase letter - at least 1 (one) number - at least 8 (eight) characters

Back-end developer

RegEx

password

Anonymous authorat Mar 28, 2023

Hard

1 vote6 runs0 comment

Count the number of matches of the RegEx `a*` in the sentence: `I went to my grandparent house`

Back-end developer

RegEx

string

Matthieu Sanchezat Feb 2, 2026

Medium

1 vote6 runs0 comment

Write a regular expression to match 'i{,4}' in a string

Back-end developer

RegEx

pattern

Matthieu Sanchezat Feb 2, 2026

Hard

0 vote167 runs1 comment

Which letters will be match by the RegEx `/\x42/gmi`

Back-end developer

RegEx

characters

Anonymous authorat Feb 6, 2024

Easy

0 vote94 runs0 comment

Write a regular expression that matches anything that is not `a`, `b` or `c`

Back-end developer

RegEx

character classes

Anonymous authorat Mar 28, 2023

21 interview questionsfor developers (2026)

Test your developer skills before an interview with 21 corrected questions on 80+ topics. Beginner, Intermediate or Expert level.

Find all the strings that match the regular expression: `/abracadabra{2,4}/gmi`

Which of the following is not a regular expression?

Write a regular expression to extract a file name from a path, except if the file is a .html file

Write a RegEx that has the same behavior as trim (JS) or strip(Python)

Write a regular expression that matches a character that repeats exactly 6 times.

Write a regular expression that matches anything that looks like an HTML tag.

Write a RegEx that will only find the word 'test' in the sentence 'I write a testimonial about this test'

Find the intruder in the following regex: `^[a-zA-Z0-9_-]+$`

Write a regular expression that matches any number in a string

Write a regular expression to match the characters . and ?

Write a regular expression that replaces all tags without content with self-closing tags

Find all the occurrences of the substring 'abracadabra' in the string 'abracadabraabracadabraabracadabra'

Write a regular expression that matches a valid email address

What does this RegEx do : `/(^\w+)(?=\.\w+)/old_$1/gm`

What does the RegEx `/[abc]/` match

Which RegEx(s) can be used to verify that a password meets these criteria: - at least 1 (one) lowercase letter - at least 1 (one) uppercase letter - at least 1 (one) number - at least 8 (eight) characters

Count the number of matches of the RegEx `a*` in the sentence: `I went to my grandparent house`

Write a regular expression to match 'i{,4}' in a string

Which letters will be match by the RegEx `/\x42/gmi`

Write a regular expression that matches anything that is not `a`, `b` or `c`