How to play
The cube has six faces, and each face is a grid of coloured stickers: 2×2, 3×3, 4×4 or 5×5. Press “Scramble and start” and the cube is mixed with random turns. Your goal is to turn the layers until each face shows a single colour again.
The clock waits for your first turn, so you can study the scramble first. Turning the whole cube to see the other sides is free: it never starts the clock and never counts as a move. With the 15-second inspection on, a countdown runs while you look and then starts the clock. When every face is one colour, the clock stops and you see your time, your moves and your best time for that size. “Free play” lets you experiment without a clock.
Controls
- Mouse: press on a sticker and drag along its row or column. The layer follows the pointer and snaps to the nearest quarter turn when you let go. Drag the empty background to turn the whole cube: sideways spins it, up or down tips it.
- Touch: the same with your finger. The page does not scroll while your finger is on the cube’s area.
- Keyboard: U D L R F B turn the up, down, left, right, front and back face clockwise, and with Shift counter-clockwise. M E S turn the middle layers, the arrow keys or X Y Z turn the whole cube, and W before a face letter makes a wide turn. Backspace undoes, Ctrl+Y redoes, N scrambles and P pauses.
- Buttons: move buttons, Undo, Redo, Reset to solved, and a box for typing a whole sequence such as
(R U R' U')6.
To turn the front face, drag along the row next to it on the top or the right face.
How it works
Notation
The letters are the standard cube notation. Each one means a quarter turn clockwise as you look straight at that face. A prime (R′, typed R') turns the other way and a 2 (R2) makes a half turn. On bigger cubes Rw (or r) turns the two outer layers together, 3Rw turns three, and 2R turns only the second layer. M, E and S are the middle layers: M turns like L, E like D and S like F. Lowercase x, y and z turn the whole cube the way R, U and F turn.
Inside the program
The program stores the colour of every sticker, six times N×N of them. A turn is a permutation: a fixed rule that moves every sticker of the turning layer to a new slot. The program builds each rule by rotating the position and the outward direction of every sticker by 90° around the layer’s axis and looking up where it lands. On screen, every sticker corner is rotated, put into perspective and painted from back to front.
A scramble uses 11 random turns on the 2×2, 25 on the 3×3, 40 on the 4×4 and 60 on the 5×5. It never turns the same layer twice in a row and never makes three turns in a row on one axis, so no turn cancels the one before it.
Why it is hard
The classic 3×3 twisty cube puzzle, for which a Hungarian patent was filed in 1975, has this many positions that can be reached by turning:
The eight corners can be in any order and seven of them can be twisted freely. The twelve edges can be in any order and eleven of them can be flipped freely. Half of the orders are impossible, because corners and edges always swap together. The 2×2 has 3,674,160 positions if you ignore how the whole cube is held. In 2010 a large computer search proved that every 3×3 position can be solved in 20 turns or fewer, counting a half turn as one.
Things to try
- Type
(R U R' U')6into the move box: these four turns, repeated six times, bring the cube back to the start. - Solve a cross on one face first (the four edges around the centre), then add the corners.
- Try the 2×2: it behaves like the eight corners of the 3×3.
- On the 4×4, look for a single flipped edge pair, a case the 3×3 never shows.
- Switch the marks to letters or shapes and solve without relying on colours.
Frequently asked questions
Can every scramble be solved?
Yes. A scramble is made only of legal turns, so turning them back in reverse order always solves the cube.
What do the letters on the stickers mean?
They are the first letter of the colour: W white, Y yellow, G green, B blue, R red and O orange. The shapes do the same job with symbols.
Is this the same timing as in competitions?
Close: competitors get up to 15 seconds of inspection, and so do you. When it runs out here, the clock starts without a penalty.
Does it work on a phone?
Yes, with touch drags or the move buttons. On the 4×4 and 5×5 the top and right faces get small on a phone, so turn the cube to bring the face you work on to the front. The 5×5 stickers are the smallest, so that cube is easier on a tablet or a computer.
Sources
- Rokicki T, Kociemba H, Davidson M, Dethridge J (2010). God’s Number is 20. cube20.org. The July 2010 computer search showing that every 3×3 position can be solved in 20 turns or fewer, with a half turn counted as one.
- World Cube Association (accessed 27 October 2026). WCA Regulations, Article A3 (Inspection). Competitors get strictly less than 15 seconds of inspection before the solve.
- Rubik E (1977). Hungarian patent HU 170062 B. Filed 30 January 1975, published 28 March 1977; record on Google Patents, classed with three-dimensional puzzles whose layers rotate. The 1975 date of the cube puzzle.