Triangle peg game: rules and the one-peg solution

How to play

1. The triangle has 15 holes in five rows and starts with 14 pegs. One hole is empty: the top one, unless you choose another.
2. A peg jumps over one neighbouring peg into the empty hole directly behind it, along any straight line of the board. The jumped peg comes off.
3. Tap a peg to pick it up. The holes it can jump into glow; tap one to jump, or tap the peg again to put it down.
4. The game ends when no jump is left anywhere on the board. The pegs still standing are your score.
5. Undo takes back the last jump, as many times as you like, even after the game has ended. Restart sets the same start again.
6. The English cross board has 33 holes in a plus shape. Pegs jump only across and up or down, and the game starts with the centre hole empty.

Controls

Mouse

Click a peg to pick it up, then click a glowing hole to jump. Click the peg again to put it down.

Touch

Tap a peg, then tap a glowing hole. Every hole is a large tap target, on both boards.

Keyboard

Tab reaches each hole; Enter or Space picks up a peg or jumps into a hole. Escape puts the peg down.

Score and progress

Your score is the number of pegs left when no jump remains: 1 peg is Genius, 2 Pretty smart, 3 Average, 4 or more Keep practicing. On the English board, one peg in the centre is Master alchemist. Games played, fewest pegs left and one-peg finishes are saved for each board in this browser when local storage is available.

Tips

• Count the jumps you have left. With 14 pegs, a one-peg finish is always exactly 13 jumps.
• A two-peg finish usually comes from two pegs stranded far apart. Bring the last pegs together before the board thins out.
• If the board looks hopeless, Undo two or three jumps instead of restarting. The mistake is usually recent.
• On the English cross, empty the four arms before the centre block, and keep the centre hole for the very last jump.

Stuck mid-game on the triangle? The game opens your current board in the Peg Game Solver, which shows the jumps that still lead to one peg.

Peg game solution: leave one peg in 13 jumps

Holes are numbered 1 at the top, 2 and 3 in the second row, 4 to 6 in the third, 7 to 10 in the fourth and 11 to 15 along the bottom, each row from left to right. With the top hole empty, these 13 jumps leave one peg.

1. 4 over 2 into 1
2. 6 over 5 into 4
3. 1 over 3 into 6
4. 7 over 4 into 2
5. 10 over 6 into 3
6. 12 over 8 into 5
7. 13 over 9 into 6
8. 2 over 5 into 9
9. 3 over 6 into 10
10. 15 over 10 into 6
11. 6 over 9 into 13
12. 14 over 13 into 12
13. 11 over 12 into 13

Opening tips that work from any start

Clear the corners early. A peg in a corner can never be jumped over, so it can only leave by jumping out itself, and that needs a neighbour beside it. Keep the pegs in one group rather than scattering them, because a lone peg with no neighbour is stuck for good. Before each jump, look at the hole you are about to empty and ask whether a later jump can fill it. If you want an easier start, empty the middle of a side (hole 4, 6 or 13): it has the most winning lines. The three inside holes, 5, 8 and 9, are the hardest starts.