Tower of Hanoi
Move the whole tower to another peg, one disc at a time, never placing a larger disc on a smaller one. Drag discs to solve it yourself with a live move counter, or press solve and watch the optimal recursive solution play out. The minimum is exactly 2ⁿ − 1 moves — the puzzle that makes exponential growth and recursive thinking tangible, and the reason the legend’s 64-disc tower would outlast the universe.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- Recursive insight: move n − 1 discs aside, move the big one, move them back on top.
- Minimum moves double (plus one) with each extra disc: 1, 3, 7, 15, 31…
- At one move per second, 64 discs take about 585 billion years.
- Runs 100% in your browser — simulations are computed locally on your device.
Related tools
3D Geometry Board
Points, lines, planes, spheres and polyhedra on an orbiting camera — slice solids with planes, unfold nets, drop the Dandelin spheres into a cone and drag everything.
Bézier Curve Playground
Drag control points and watch De Casteljau’s algorithm construct a Bézier curve step by step.
Central Limit Theorem Demo
Sample from any lopsided distribution and watch the averages pile up into a bell curve.
Conway’s Game of Life
Paint cells and watch Conway’s cellular automaton breed gliders, guns and oscillators.
Dynamic Geometry Board
Construct with points, lines, circles and transformations, then drag anything — the construction stays true, and a checker tells you which relations are theorems.
Fantasy Map Generator
Roll a seed and get a continent: coastlines, mountains, rivers, biomes and named towns, ready for your campaign.