Rule of the Square
Use an imaginary square to decide quickly whether a king can catch a running pawn.
Why This Matters
- Count how many moves the pawn needs to promote. That number helps make the sides of the square.
- If the defending king can step inside the square, it can usually catch the pawn.
- The rule is a shortcut, but you should still check the actual moves when kings are close.
Objectives
- Draw or imagine the square of a pawn race.
- Decide quickly whether the king is inside the square or outside it.
- Check your square idea by playing the race out move by move.
Guided Interactive Lesson
Step 0 of 6
Try to play move 1:(Expected idea from lesson line)
Lesson Line
- Kd4
- c3
- Kxc3
- Kg7
- Kd4
- Kg6
Practice Positions
Find the move yourself — the answer stays hidden until you solve it or reveal it.
Practice 1 of 3
White to move. Play out the race and show that the king is inside the square.
Practice 2 of 3
White to move. Play the race and prove that the king is outside the square.
Practice 3 of 3
Rook pawns have a funny-shaped race too. Play it out and show the king still catches this one.
Mini-Game
Play this with a partner. Before each king move, point to the imaginary square of the pawn and say whether the king is inside it or outside it.
Printable Move-by-Move Boards
Print one board per step to review the full sequence offline.
Open printable version