The six face turns: R, L, U, D, F and B
Rubik's cube notation is the shorthand cubers use to write down moves, so any solution or algorithm can be shared as a line of letters. It is often called Singmaster notation, after the mathematician David Singmaster who devised it. Each capital letter names one side of the cube, as seen from where you are holding it:
| Letter | Face | Where it is |
|---|---|---|
| R | Right | the right-hand column, facing your right |
| L | Left | the left-hand column, facing your left |
| U | Up | the top layer |
| D | Down | the bottom layer |
| F | Front | the side facing you |
| B | Back | the side facing away from you |
A letter on its own means turn that face a quarter turn clockwise, as if you were looking straight at that face. This is what each one looks like from the front (the blue squares are the pieces that move):
front row slides left
front row slides right
rolls up at the front
rolls down at the front
clockwise, like a clock
looks anticlockwise from the front
Prime (') and 2: anticlockwise and half turns
Two marks can follow a letter. Using the right face as the example:
| Move | Say it | What to do |
|---|---|---|
| R | “R” | right face a quarter turn clockwise (the front of it goes up) |
| R' | “R prime” | right face a quarter turn anticlockwise (the front of it goes down) |
| R2 | “R two” | right face a half turn, 180°; either direction gives the same result |
The part that trips everyone up
“Clockwise” always means clockwise when you look straight at that face, not as you see it from the front. So:
- U moves the front row of the top layer to the left, but D moves the front row of the bottom layer to the right.
- R rolls the right column up at the front, but L rolls the left column down at the front.
- F turns like a clock hand as you face it, but B looks anticlockwise from the front.
Keep the same face towards you the whole time you follow an algorithm: the letters only make sense if the cube does not turn in your hands.
Wide moves: r, l, u, d, f, b (Rw, Lw…)
A lowercase letter means a wide turn: that face and the middle slice next to it turn together, as one block of two layers.
It is also written with a w: r and Rw mean the same thing on a 3×3 cube. The direction is the same as the
capital letter, so r turns like R, r' like R' and r2 is a half turn.
Wide turns appear in several last-layer algorithms, for example the Chameleon OLL r U R' U' r' F R F'.
On bigger cubes such as the 4×4, Rw is the two outer right layers and a number in front (3Rw) says how many layers to turn.
Slice moves: M, E and S
| Move | Slice | Turns the same way as |
|---|---|---|
| M | Middle: between L and R | L (the front of the slice goes down) |
| E | Equator: between U and D | D (the front of the slice goes right) |
| S | Standing: between F and B | F |
M', E', S' and M2, E2, S2 work the same way as for faces.
M moves are the heart of the Roux method's last step and of the H-perm M2 U M2 U2 M2 U M2.
Cube rotations: x, y and z
These turn the whole cube in your hands; no layer moves against another, so they do not count as moves.
| Rotation | Turns the whole cube the way… |
|---|---|
| x | R turns (the front goes up to the top) |
| y | U turns (the front goes to the left) |
| z | F turns (the top goes to the right) |
As usual, y' is the other way and y2 is a half rotation. You will most often see
y or y' in F2L and OLL algorithms, to bring the right slot to the front.
How to read an algorithm
An algorithm is a fixed sequence of moves that does one job, read from left to right. Take the Sune, a last-layer algorithm:
Sune
Right clockwise, top clockwise, right anticlockwise, top clockwise, right clockwise, top half turn, right anticlockwise. It turns three top corners without touching the first two layers.
Brackets and repeats
Brackets group moves that flow together (“triggers”), to make long algorithms easier to remember:
(R U R' U') (R' F R F'). A number after a bracket means repeat it: (R U R' U') ×3, sometimes
written (R U R' U')3, is the four moves done three times. Spaces are optional, so RUR'U' is the same as R U R' U'.
Reversing an algorithm
To undo an algorithm, read it backwards and swap every turn for its opposite (half turns stay the same). The reverse of
R U R' U' is U R U' R'; doing an algorithm and then its reverse leaves the cube exactly as it was.
Triggers with names
A few short sequences come up so often that they have nicknames:
The “sexy move”
The most common trigger of all. Six in a row bring the cube back to the start.
The sledgehammer
Used in many OLL algorithms. It also returns to the start after six repeats.
How moves are counted
When people say a solution is “20 moves”, they are usually counting in the half-turn metric (HTM): any turn of one face, a quarter or a half, is one move. In the quarter-turn metric (QTM) a half turn counts as two, and the slice-turn metric (STM) also counts an M, E or S turn as one move.
Every position of the 3×3 cube can be solved in 20 moves or fewer in the half-turn metric (proven in 2010) and in 26 or fewer in the quarter-turn metric (proven in 2014). That limit is known as God's number. The Rubik's cube solver on this site counts in the half-turn metric: its Shortest mode usually finds about 20 moves and never more than 22.
Scramble notation
A scramble is written in the same notation, using only face turns, for example R2 D' B U2 L F' ….
It is applied to a solved cube held with white on top and green in front, the standard orientation in competitions.
The cube timer on this site writes a new random scramble for every solve and draws what the cube should look like after it.
Questions people ask
What does R U R' U' mean on a Rubik's cube?
Turn the right face clockwise, the top face clockwise, the right face anticlockwise, then the top face anticlockwise, in that order. Cubers call it the “sexy move”; it is used to put in the white corners in the beginner method, and doing it six times in a row brings the cube back to where it started.
What does the apostrophe mean in Rubik's cube notation?
An apostrophe, said “prime”, means turn that face a quarter turn anticlockwise, as you look straight at it. So R' is the opposite of R, and doing R then R' changes nothing.
What does a 2 after a letter mean, like R2?
Turn that face twice: a half turn of 180 degrees. Either direction gives the same result, so R2 and R2' mean the same thing.
What is M in Rubik's cube notation?
M is the middle slice between the left and right faces. It turns the same way as L: the front of the slice goes down. E is the slice between the top and bottom (turns like D) and S is the slice between the front and back (turns like F).
What does a lowercase letter like r or Rw mean?
A wide turn: the face and the middle slice next to it turn together, two layers at once. On a 3×3 cube r and Rw mean the same thing, and r is the same as R and M' done at the same time.
What do x, y and z mean in cube notation?
They turn the whole cube in your hands, not one layer. x turns it the way R turns, y the way U turns and z the way F turns. They do not count as moves.
How do you reverse a Rubik's cube algorithm?
Read it backwards and swap every turn for its opposite: R becomes R', R' becomes R, and half turns stay as they are. The reverse of R U R' U' is U R U' R'.
Sources
Written in our own words. The move sequences are the standard ones cubers share, and every one on this page is checked on this site's own cube engine. These pages go further: