Learn to code by solving challenges

Bite-sized lessons, code in your browser and instant feedback. Free.

Nothing to install — write and run Python and JavaScript right on the page.

Every challenge is checked automatically, so you know right away if you got it.

Earn XP for every lesson and keep your daily learning streak alive.

Courses

The most popular first language: variables, conditions, loops and functions.

The language of the web: variables, functions, arrays and logic basics.

Build your first web page: tags, styles and lists.