How many players can play?

This version supports 2 to 4 players. Each player can independently be set to Human (local pass-and-play) or AI with Easy, Medium, or Hard difficulty.

What is the best strategy for Dots and Boxes?

The key strategies are: always complete a box when you can (you get a bonus turn), avoid drawing the third side of a box (your opponent will complete it), and learn chain strategy — sacrifice a small chain of 2 boxes to gain control and capture all remaining long chains.

What board sizes are available?

Four board sizes: 3×3 (9 boxes), 4×4 (16 boxes), 5×5 (25 boxes), and 6×6 (36 boxes). Larger boards offer deeper strategy and longer games.

What do the AI difficulty levels mean?

Easy AI picks moves randomly. Medium AI prioritises completing boxes and avoids giving boxes away, but doesn't plan ahead. Hard AI uses advanced chain strategy to control the endgame and maximise its score.

Play Dots and Boxes Online

Q: What is Dots and Boxes?

Dots and Boxes is a classic pen-and-paper strategy game for 2 or more players. Players take turns drawing a line between two adjacent dots. When a player draws the fourth side of a 1×1 box they score that box and take another turn. The player with the most boxes at the end wins.

Take turns drawing lines between dots. Complete a box to score a point and earn a bonus turn. The player with the most boxes wins!

Player Setup

Players:

Player 1’s turn

What Is Dots and Boxes?

Dots and Boxes (also called Boxes, Dots, Pigs in a Pen, or La Pipopipette) is one of the most popular pen-and-paper games ever created. It was first analysed mathematically by the French mathematician Édouard Lucas in the 19th century and has been a playground favourite around the world for over a hundred years.

Despite its simple rules, the game hides surprising strategic depth. At the competitive level, mastery requires understanding chain theory, double-dealing, and nimstring analysis — concepts borrowed from combinatorial game theory.

Rules

The board is a grid of dots. Players take turns drawing a single horizontal or vertical line between two adjacent dots.
When a player draws the fourth (closing) side of a 1×1 box, they score that box (marked with their colour/initial) and take another turn.
A single move can complete two boxes at once (the line is shared between them), scoring both.
The game ends when every possible line has been drawn.
The player with the most boxes wins. Ties are possible.

How to Play This Version

Choose a board size (3×3 up to 6×6 boxes).
Set the number of players (2–4) and choose Human or an AI difficulty for each.
Click or tap between two adjacent dots to draw a line.
Completed boxes light up in that player’s colour. The current scores are shown above the board.
Click New Game to restart with the current settings.

Strategy Tips

1. Always Take Free Boxes

If a box has three sides drawn, always complete it. You score a point and get a bonus turn. This seems obvious, but beginners sometimes miss boxes hiding in plain sight.

2. Avoid Drawing the Third Side

Drawing the third side of a box is a “gift” — your opponent will immediately complete it. In the early game, try to play lines that leave every box with at most two sides drawn.

3. Chain Strategy

A chain is a line of boxes each missing only one side. When you complete the first box in a chain, you get a bonus turn and can keep going along the chain, capturing the entire sequence.

4. The Double-Cross (Double-Deal)

When you control the last move before a long chain, you can deliberately leave two boxes at the end of the chain unclaimed (a “double-cross”), forcing your opponent to take them and then open the next chain for you. This sacrifice of 2 boxes can win you dozens.

5. Count Chains & Control Parity

In endgame theory, the player who can force their opponent to open the last long chain wins. Count the number of long chains (3+ boxes) — if the count is odd, the first player to face a chain-opening usually loses.

Dots and Boxes vs Other Games

vs Slitherlink: Both draw lines on a dot grid, but Slitherlink is a single-player logic puzzle while Dots and Boxes is competitive strategy.
vs Go: Both use territory-claiming on a grid, but Go uses stone placement while Dots and Boxes uses line drawing.
vs Checkers: Both are classic 2-player strategy games, but Dots and Boxes scales to 4 players and centres on territorial control rather than piece capture.

Frequently Asked Questions

A classic pen-and-paper game. Players take turns drawing lines between dots. Complete the fourth side of a box to score it and take another turn. Most boxes wins.

This version supports 2 to 4 players. Each can be set to Human or AI (Easy, Medium, or Hard).

Always complete boxes when possible. Never draw the third side of a box if you can avoid it. In the endgame, learn chain strategy and the double-cross technique to control who opens chains.

Easy picks random moves. Medium grabs free boxes and avoids giving them away. Hard uses chain analysis and the double-cross strategy to play at near-optimal level.

3×3, 4×4, 5×5, and 6×6 boxes (meaning 4×4 to 7×7 dots).

More Puzzle & Strategy Games

If you enjoy Dots and Boxes, try these other free games on our site:

Checkers

Classic draughts with 3 AI levels or pass-and-play vs a friend.

Gomoku

Five in a row — place stones and connect five to win.