How to play Dots and Boxes

1 player vs computer, or 2 online

Own more of the twenty-five boxes than your opponent when every line has been drawn. A box is yours if you drew its fourth side.

The rules, step by step

1. 1

   The board is a grid of dots, five boxes across and five down. A move is drawing one line between two dots that are next to each other.

2. 2

   If your line completes the fourth side of a box, that box is yours — and you draw another line straight away.

3. 3

   One line can complete two boxes at once. You still get one extra turn, not two.

4. 4

   If your line completes nothing, your turn is over.

5. 5

   There is no passing. Play continues until every line is drawn, so the boxes always add up to twenty-five and there is no draw.

Three tips that change how you play

• Count the safe moves before you make one. A safe line is one that leaves no box with three sides. Early on almost everything is safe; the game turns on who runs out first, and you can see it coming several moves ahead if you look.
• Learn the double-cross. When you are handed a chain, taking all of it means you have to open the next one. Take all but the last two boxes, then draw the line through the middle of those two so your opponent has to take them — and open the next chain themselves.
• Make chains long, or make them few. If you will be the one opening chains, you want as few as possible. If your opponent will be, you want to keep the long ones long. Every safe move you make is quietly deciding which of those two boards you are building.

Giving two boxes away to win four

Late in a game there are two chains left: a short one of two boxes, already open, and a long one of five, still closed. It is your move and the short chain is sitting there. Take both boxes and you have gained two — but now it is still your turn, every remaining line opens the long chain, and your opponent takes all five. You are three down. Instead, take neither. Draw the line across the middle of the short chain, so both of its boxes get a fourth side at once and your turn ends. Your opponent gets those two boxes, and then they are the one holding a board with nothing safe on it. They open the long chain; you take all five. You gave away two to take five, and you are three up instead of three down — a six-box swing out of a move that looked like throwing boxes away.

Three mistakes that cost beginners the game

Taking every box on offer.

This is the whole game in one mistake. Taking the last two boxes of a chain leaves you with the move, and the only moves left are ones that open the next chain. Give those two back and the problem is theirs. Against anybody who knows this, greedy play loses even from a winning position.

Drawing the third side of a box to see what happens.

What happens is that your opponent takes it, and everything behind it. A box with two sides is one line away from being given away, so before you draw anything, check both boxes that line touches. The board is doing the counting whether you are or not.

Playing the opening at random because nothing matters yet.

It looks like nothing matters and it decides the endgame. Every early line either joins two boxes into a longer chain or does not, and the number and length of the chains is exactly what the endgame is fought over. The opponent on hard is choosing between safe lines on that basis from the first move.

Common questions about Dots and Boxes