Dots and Boxes
Connect dots, complete boxes – who claims the most?
How to Play
Goal
Complete as many boxes as possible by drawing lines between adjacent dots.
Gameplay
Click an empty line between two dots. If you complete the 4th side of a box, you score a point and take another turn.
Winner
When all lines are drawn, the player with the most boxes wins. Equal scores result in a draw.
Strategy & tips
The first moves barely matter; the endgame decides everything. While no box is close to completion, every line is equally good. It gets interesting the moment a box receives its third line — that is when the real game starts.
The winner is whoever forces the opponent to open the first long chain. Chains of three or more boxes always fall entirely to whoever enters them first. The player who still has a neutral move left last takes them all.
Hence the key technique: deliberately decline the last two boxes of a chain. Take everything and you must open the next chain yourself. Leave two behind and you hand them over — and receive the next, larger chain in return.
Variants
Larger grid
More dots mean longer chains and make the parity calculation the single decisive factor.
Uneven board
On a grid with unequal side lengths the parity shifts and familiar openings stop working.
No extra turn
Completing a box does not earn another go. Chain tactics vanish entirely and the game becomes purely arithmetic.
How it works
1. Create a game
Click "Create Game" and receive a 6-digit code.
2. Share the code
Share the code with your friends – via WhatsApp, Telegram, or just tell them.
3. Play instantly
Your friends enter the code and you start playing immediately. No login required!
Origin
The game was described in 1889 by the French mathematician Édouard Lucas as La Pipopipette — the same Lucas behind the Towers of Hanoi.
What looks like a children's game is mathematically deep: the full theory of chain lengths and parity fills books. Elwyn Berlekamp devoted an entire monograph to it.
Frequently asked questions
Who moves after completing a box?
You do, again. That is why entire chains fall to the same player in a single turn.
Why would I leave boxes on purpose?
Because otherwise you are forced to open the next chain. Sacrificing two boxes costs two points and often gains five or more.
Who wins?
Whoever has claimed more boxes at the end. Every box gets filled, and a draw is possible on a board with an even number of boxes.