🗼 Tower of Hanoi
Move the whole tower to the right-hand peg. One disc at a time, and never put a bigger disc on top of a smaller one. Sounds easy — then you try it with six.
Tower of Hanoi puzzle
Moves0
Best possible7
Your best—
Time0:00
Move the whole tower to the right-hand peg.
How to Play
- Moving a disc
- Tap a peg to lift its top disc, then tap another peg to put it down. Tap the same peg again to change your mind. On a keyboard, 1 2 3 pick pegs and U undoes.
- The one rule
- A disc can only go on an empty peg, or on top of a bigger disc. Never on a smaller one.
- Best possible
- There's a shortest answer, and the game knows it: 2 × 2 × … − 1. Three discs take 7 moves, four take 15, five take 31 — each extra disc doubles the work and adds one. Eight discs need 255 moves!
- Show Me
- 👀 Show Me plays the perfect solution so you can watch the pattern. Try it with three discs first — the same shape repeats inside itself, which is the whole secret.
- The trick
- To move 4 discs you first move the top 3 out of the way, move the big one, then move those 3 back on top. To move 3 you do the same with 2. Every big problem is just a smaller one done twice.
- The legend
- A story says monks are moving 64 golden discs, and the world ends when they finish. At one move a second that would take about 585 billion years — so there's no rush.