Dots and Boxes

How to play Dots and Boxes

Dots and Boxes is a pencil-and-paper game for two players, played on a grid of dots. Players take turns connecting two neighboring dots with a line, across or down.

• Draw one line per turn between two dots next to each other.
• Close a box to claim it. If your line draws the fourth side of a box, the box is yours and you must draw another line. One line can close two boxes at once.
• Keep going while you close boxes. Your turn ends when you draw a line that doesn't close a box.
• The game ends when every line is drawn. Whoever claimed more boxes wins.

Playing on Poozee

• Board sizes: 3x3 (9 boxes, 24 lines), 4x4 (16 boxes, 40 lines) or 5x5 (25 boxes, 60 lines). Only the 4x4 board can end in a tie.
• vs Computer: you're red, and you take turns drawing first, game by game. Easy grabs every box it can but often draws carelessly; Medium never gives a box away while it has a safe line; Hard counts chains and plays the endgame perfectly.
• 2 Players: Red and Blue share one screen and take turns.
• To draw a line, tap or click near it: every spot on the board belongs to the closest line, so you don't have to hit it exactly. With a keyboard, Tab to the board, move with the arrow keys and press Enter.
• The lines of the latest turn are highlighted, so you can see what your opponent just did, even when the computer takes a whole run of boxes.
• Hint (against the computer) shows the line the Hard computer would draw for you. Undo takes back your last line, along with the computer's reply (in 2 Players, the last line drawn).
• Your games won, lost and tied are kept for each board size and level in this browser.

Strategy basics

1. Don't draw the third side of a box. Whoever moves next just takes it. Early on, only draw lines that leave every box with two sides or fewer.
2. Know when the safe lines run out. At that point the open boxes form chains and loops, and every line gives something away.
3. Make your opponent open the long chains. A chain of three or more boxes is a long chain, and the player who has to open them usually loses.
4. Take all but two. When your opponent opens a long chain and more are waiting, take every box except the last two, then hand those back. Your opponent has to open the next chain for you.

Our Dots and Boxes strategy guide explains each idea with worked examples, the long chain rule for every board size, and how much each one wins in games between the computer levels.

Pro tip: On the 3x3 board, the second player wins with perfect play: Poozee's solver checked every possible game. When you go first against Hard, you can only win if it slips in its first couple of lines: from the fifth line of the game on, it plays perfectly.