Learn frontend testing.
one lesson at a time

Everything from what to test and how to think about it, to modern testing tools and real code challenges you solve in the browser.

Start the free Vitest courseBrowse all courses and lessons

Most popular starter courses:

New to testing? Take the fundamentals course first.
Already comfortable with Jest or Vitest? Check the React testing course.
Need something more advanced? See the list below.

Free

Jest & Vitest fundamentals

Test structure, matchers, async code and mocking. The foundation everything else builds on.

Start with the basics

React Testing Library

Render components, query the DOM the way a user would, and test interactions with confidence.

Learn React testing

Vitest Browser Mode

The future of frontend testing (probably!)
Test your React components in a real browser instead of jsdom. Covers setup, locators, and where it beats the classic way of testing.

Take the course

All courses & challenges

Everything on the site, including the challenge sets that put your knowledge on the spot.

01

Jest/Vitest Testing Fundamentals

Learn the basics of how to test with Jest or Vitest. This course covers the main features for writing assertions, tests, mocks, async testing, and more

02

React Frontend Testing

Course on testing React applications, using React Testing Library (with Jest or Vitest). Covers everything you will need to know to be able to test your Frontend applications

03

Finding elements with React Testing Library queries

Become familiar with all the ways to find elements in your rendered components with React Testing Library. This is a more in depth look at all the getBy, findBy and queryBy functions

04

React Testing Library DOM Matchers

Course covering all DOM matchers in React Testing Library, including `.toHaveAttribute()`, `.toBeChecked()` - learn them all to make your tests cleaner and easier to write

05

React Test Challenges

Challenge

Use what you learned in the other courses and see if you can fix these broken tests in our set of tricky React testing challenges. If you get stuck you can always reveal some hints to guide you along the way.

06

Vitest and Jest Test Challenges

Challenge

Take on our challenges to fix some broken tests - testing your knowledge of how Jest or Vitest works.

07

Vitest Browser Mode

Learn everything you need to know to get up to speed with Vitest Browser Mode, to run your tests in a very realistic, fast and (optionally) visual way!

Think your React testing is already solid?

Take the React testing challenge and find out, or read the blog first.

Try the testing challengeRead the blog