About Dots and Boxes Online
Play dots and boxes online with a friend: pick a 3×3, 4×4 or 5×5 board, then send an invite link or a six-character code, or use quick match to play whoever is waiting. Both players see every line as it is drawn, and a rematch swaps who starts.
Dots and Boxes is a pencil-and-paper classic for two players. Take turns joining two neighbouring dots with a line. Draw the fourth side of a box and it is yours, and you must draw again. When every line is drawn, the player with more boxes wins.
Also called: boxes game, pigs in a pen, dot game.
How to play Dots and Boxes
- Choose a board: 3×3, 4×4 or 5×5 boxes. Yellow moves first; against the computer choose 1st or 2nd and a level.
- Tap or click between two dots to draw a line. The tap area is generous: aim anywhere near the gap.
- If your line completes a box (its fourth side), the box fills with your colour and you must move again.
- If your line completes nothing, it is your opponent’s turn.
- The game ends when every line is drawn. Whoever owns more boxes wins.
Rules
- Lines join dots that are next to each other, across or down, never diagonally.
- One line can complete two boxes at once; both are yours, and you still move again only once.
- You must draw a line on your turn, even if every line left gives boxes away.
- On the 4×4 board (16 boxes) a draw is possible; 3×3 and 5×5 always have a winner.
- Undo against the computer takes back your last line and the computer’s replies; with a friend it takes back one line.
Dots and Boxes tips and strategy
- Don’t draw the third side of a box if you can help it. That hands your opponent the box, and often a whole chain of them.
- As the board fills, it breaks into chains (rows of boxes that fall one after another) and loops. Eventually someone has to open one. Count them before that moment arrives.
- The long chain rule: the first player wants the number of dots plus the number of long chains (three or more boxes) to be even. So on the 3×3 and 5×5 boards (16 and 36 dots) the first player wants an even number of long chains, and on 4×4 (25 dots) an odd number. The second player wants the opposite. Steer the safe moves to get the count you need.
- Double-dealing: when your opponent opens a long chain, take all but the last two boxes, then draw the line at the far end. You give away two boxes, but your opponent must then open the next chain for you.
- When you must open something, open the shortest chain first, and open a two-box chain in the middle so your opponent can’t double-deal it.
Dots and Boxes questions
What happens after I complete a box?
The box becomes yours and you draw again straight away. A single turn can capture a whole chain of boxes, one line at a time.
How does the Hard computer play?
Hard never gives boxes away early, and once the board breaks into chains and loops it solves the ending exactly: it double-deals to keep control when that wins more boxes, and it fights the parity battle over who must open the first long chain.
Why did the computer leave two boxes for me?
That is double-dealing. By giving you two boxes, it forces you to move next, which usually means opening the next long chain and giving the computer more boxes in return.
Which board size should I play?
3×3 is quick and good for learning. 4×4 is the standard game. 5×5 has more chains and loops and rewards careful counting.
Is my game saved?
Yes. The game in progress, including the board size, is saved in your browser after every line, and your record against each computer level is kept.
Is Dots and Boxes free to play?
Yes. Dots and Boxes on Kultured Arcade is completely free: no download, no account and nothing to buy. It runs in any modern browser on a phone, tablet or computer.
Can I play Dots and Boxes on my phone?
Yes. The game fits your screen and works with touch as well as a mouse and keyboard, on iPhone, Android, tablets and computers.