Cellular Automaton
A fun way to create interesting patterns based on simple rules.
CSS Diner
Learn and practice CSS selectors in an interactive game.
OverTheWire Wargames
Learn and practice hacking/security concepts in the form of fun-filled games.
Binary Birthday Game
Guess a person's birthday using only 5 binary bits.
Caesar Cipher
Create encrypted messages using this simple cipher.
Number Guessing Game
Play this simple game against a friend or the computer.
Flappy Bird
This popular game is always a fun time. Put your own spin on it!
Snake
Create your own version of this popular game.
Yoda Speak
Translate plain old English into Yoda's way of speaking.
Joke Bot
Have some good jokes? Make a bot to tell them! Or, get some jokes from an API.
SQL Murder Mystery
Can you find out whodunnit?
Hangman (or Snowman)
Put your own spin on this classic word game.
Tic-Tac-Toe
Here is a shorter description.
Bubble Sort
Sharpen your skills by coding this simple sorting algorithm.
Tower of Hanoi
Code a solver for this famous puzzle using recursion.
Insertion Sort
Sharpen your skills by coding this simple sorting algorithm.
Calculator
Create a basic or advanced calculator.
Coin Toss
Need to flip a coin? Write a program for that!
Timer
Create a useful tool for toothbrushing, cooking, and more!
Palindrome checker
Enjoy word puzzles? This one might be fun for you!
Regex Crossword
A crossword puzzle game, where the crossword clues are defined using regular expressions.
md5 cracker
Write a program to decrypt this common hashing algorithm.
Chinese Zodiac Calendar
Display each animal sign and tell people which sign they are.
Screeps
MMO sandbox game for programmers
Dice Roller
Need to roll some dice? Write a program for that!
Number Pyramid
Write a program to display a symmetrical pyramid of numbers.
VIM Adventures
An online game for learning how to use the vim text editor.
Sudoku Solver
Write a program to solve Sudoku puzzles.
Fibonacci Sequence
This simple number sequence has a lot to offer coders, from simple iteration to recursion and dynamic programming.
Pong
Create your own version of this popular game.
Unit Converter
Create a handy tool for converting temperature, weight, time, or distance.