Moves 0
Fewest possible 15
Best –
How to play
Goal
Move the whole tower from the left peg to the right peg.
Rules
- Move one disc at a time. Only the top disc of a stack can move.
- A disc can never sit on top of a smaller disc.
How it works
- Tap a peg to lift its top disc, then tap another peg to drop it there.
- Tap the same peg again to put the disc back down.
- On a keyboard, press 1, 2 and 3 for the three pegs.
- Choose 3 to 7 discs. Each extra disc doubles the work: the fewest possible moves is 2n − 1.
Tips
- The smallest disc moves on every second turn, always circling in the same direction.
- With an odd number of discs, move the smallest disc to the right first. With an even number, move it to the middle first.
- On the turns in between, make the only legal move that does not touch the smallest disc.
The history of Tower of Hanoi
French mathematician Édouard Lucas invented the puzzle in 1883. He sold it with a legend about monks moving 64 golden discs, and said the world would end when they finished. At one move a second, that would take about 585 billion years.