heyloTHE HEYLOBUDDY PLAYBOOK
Square-ItRules, tips & a good first game.
Turn a grid of dots into a contest over territory. Draw the last side of a box to claim it, while thinking ahead about the chain of boxes your next line might give away.
YOUR CONTROLS
Tap or click the line between neighboring dots. Choose Classic or Roll & Rule before starting, then select the grid size.
Classic rules
Players alternate drawing one horizontal or vertical line. Completing the fourth side of a box earns one point and another turn. One shared line can complete two boxes at once. When a line closes no box, the turn passes. When every line is drawn, the highest score wins; equal scores are a draw.
Grid size is measured in dots
A 3×3 grid of dots contains four boxes, while 5×5 dots contain 16 and 10×10 dots contain 81. Start with a small grid to learn how extra turns work. Larger boards give you more room to build chains, but a single mistake can hand over many boxes.
Roll & Rule
This variant uses a die to determine how many lines you may draw that turn. Completed boxes still score points. If your roll exceeds the number of available lines, the turn passes. Do not assume the Classic extra-turn strategy applies unchanged: the roll and the remaining lines shape your choices.
A useful first tactic
Early in Classic, avoid drawing the third side of a box when safe alternatives exist. Later, look beyond the box directly in front of you. Taking one box may force you to open a chain for your opponent, so count the boxes in that chain before choosing your line.
Computer and online matches
Both rule sets offer computer play. For a friend, create a room and share its code. The host starts first in online matches, and you play first against the computer. Online rooms last 24 hours. The computer match is saved in the current tab; a shared room does not pause when you leave its screen.
Read the boxes on both sides of a line
In Classic Square-It, one move can affect two neighboring boxes. Count their existing sides before you draw. This habit is more useful than looking only for a line that seems safely far from your opponent.
One line, two boxes, two points
In the position below, both boxes already have three sides. The missing shared middle line is the fourth side of each. Drawing it claims both boxes for two points. Because your move completes a box, Classic also lets you take another turn if moves remain.
The opportunity comes from the shared edge, not from drawing two lines. You place one line and receive credit for every box it closes. On a larger board, inspect both sides of an interior line before deciding what it earns or gives away.
How a harmless-looking line gives away a box
Imagine a single box with only its top and left sides drawn. You add the bottom side. You have completed no box, so your turn ends. The opponent can now add the right side, claim the box, and continue playing.
When another move would leave every adjacent box with fewer than three sides, that alternative avoids this immediate gift. This is what players mean by a “safe” early move. It describes the immediate position; it is not a promise that the move wins the entire game.
When there are no safe moves left
Late in a game, every available line may offer a box to someone. Stop asking whether you can avoid giving away anything and compare how many boxes each opening could release. Trace the likely extra turns: after the opponent closes the first box, which line can they draw next, and does it close another?
If one choice releases a two-box chain and another releases a five-box chain, the immediate cost is different. But choosing the shorter chain is not a universal winning rule. The current score, other chains, and who controls the remaining moves can change the longer-term result. Count the consequences before treating a small sacrifice as automatically best.
Practice on dots, not a guessed board size
A 3×3 grid of dots creates four boxes, because there are two gaps across and two down. A 5×5 dot grid creates sixteen. Use the small board to practice extra turns and double-box moves before working through long chains.
These examples describe Classic. In Roll & Rule, the die determines the line allowance and changes turn planning. Keep the geometric habit of checking both sides of a line, but use that mode’s turn rules rather than assuming the same extra-turn sequence.
Check yourself: if your line completes no box, do you get another Classic turn?
No. The turn passes. Completing at least one box is what earns the extra Classic turn.
Try Classic on a small board → Before each move, predict who will play next.
A couple of good questions
Can I draw diagonal lines?
No. Only horizontal and vertical connections between adjacent dots are legal.
What if my die roll is too large?
In Roll & Rule, a roll larger than the number of lines remaining passes the turn.
Worked examples checked against the current game rules · November 8, 2026