Rules
How to play
The rules are simple; the tactics are not. Here's everything you need to know about every mode.
board size
3×3 · Classic
Win: 3 in a row
The classic game. Three marks in a horizontal, vertical, or diagonal line wins. With perfect play on both sides, the game ends in a draw.
board size
4×4 · Bigger
Win: 4 in a row
Four in a row on a four-by-four board. Every row, column, and diagonal must be fully claimed — draws are more common, wins are sweeter.
board size
5×5 · Strategic
Win: 4 in a row
Four in a row on a five-wide board. More space means more ways to build two threats at once — this is where fork tactics shine.
modes
Game modes
Computer
Play against the AI on 3×3, 4×4, or 5×5. Easy plays randomly. Medium takes wins and blocks yours.Impossible plays a perfect game on 3×3 — you can at best draw.
2 Player
Hot-seat play on one device. Set both names, then take turns. The scoreboard tracks wins, losses, and current streaks for the session.
Ultimate
Nine mini-boards arranged on a big board. Win a mini-board and it's claimed on the big board. The forced-move rule: wherever you place your mark, your opponent must play in the matching mini-board. If that mini-board is full or won, they can play anywhere. Three claimed mini-boards in a row wins the game.
Online
Create a room and share the six-character code with a friend. They join, and you play peer-to-peer over the internet. No accounts, nothing to install.
controls
Controls & hotkeys
- Arrow keysMove focus on the board
- Enter / SpacePlace a mark
- UUndo last move
- RRestart the game
- NNew game with current settings
- MToggle sound
Scoring & streaks
A win adds one to the winner's score and grows their current streak. A loss or a draw resets the streak. Best streak is the longest run you reach in a session. Lifetime totals (games played, wins, losses, draws) are saved in your browser and survive reloads.
Puzzles
Win-in-1: it's your turn, find the winning move. Win-in-2: find a move that forces a win no matter what your opponent does. Daily: a new puzzle each day, selected by the date.
Rules are easy. Winning isn't.
Read the strategy guide, then put it to the test.