hackerrank.com

A fun social platform for hackers to solve interesting puzzles, build quick hacks, code game bots and collaborate to solve real-world challenges.

Free Web

CodeFights

Duel with friends and foes in head-to-head programming battles!.

Free Personal Web

Codewars

Achieve code mastery through challenge. Improve your skills by training with others on real code challenges Kata In our dojo, kata are real code challenges...

Free Self-Hosted

CheckIO

CheckiO is expanding the world’s code literacy through gameplay. We always wanted to create the most entertaining game where gaming and coding experiences are interlaced, where there is no border between playing and learning new skills.

Free Open Source Web Pycharm WebStorm

Kattis

Kattis helps companies make safer recruitments and attract the best developers with its dynamic challenge platform. With Kattis companies make sure developers make...

Commercial Web

Geektastic

Unique peer-reviewed code challenges for deep insight into candidate's technical skills and abilities.

Commercial Windows iPhone Chrome OS

Vim Adventures

VIM Adventures is an online game based on VIM's keyboard shortcuts (commands, motions and operators). It's the "Zelda meets text editing" game.

Commercial Web

Screeps

Learn to code JavaScript by playing game. This game claims to be the world’s first MMO strategy sandbox game for programmers.

Commercial

Hackerearth

a social and community platform for students and developers for solving programming puzzles, sharing notes and practicing concepts with the online editor, live...

Free Web