Rubik’s Cube Notation Explained: F, F’ and F2
Solitaire Craft guide. Updated 13 November 2026.
Every cube guide writes turns as letters. Once you can read them, you can follow any guide, video or solver. This page explains the whole system with examples.
The six faces
The letters are the first letters of the faces: U is up (top), D is down (bottom), L is left, R is right, F is front and B is back. Hold the cube still, with one face toward you, and name the faces from where you stand.
A letter on its own is a clockwise quarter turn
When you see F, turn the front face a quarter turn clockwise, as if you were looking straight at it. This is the key rule. For the right face, clockwise means clockwise as you look straight at the right face, which means the front edge moves up. The same goes for every face.
An apostrophe means anticlockwise
The mark after a letter, called a prime, reverses the direction. F’ turns the front face a quarter turn anticlockwise. If you do F and then F’, the cube is back where it began. This pair is the first example of an undo.
A 2 means a half turn
F2 turns the front face twice, which is a half turn. It does not matter which way you turn, because a half turn is the same in both directions.
Reading a sequence
A sequence is read from left to right. For example, R U R’ U’ means: turn the right face clockwise, turn the top face clockwise, turn the right face anticlockwise, then turn the top face anticlockwise. Many guides call this the right hand trigger.
How to undo a sequence
To take back a sequence, write it backwards and flip every turn. The reverse of F L R’ R’ F B U is U’ B’ F’ R R L’ F’. A 2 stays a 2, because a half turn is its own reverse.
Other letters you will meet
- M, E and S turn a middle slice. M is the slice between left and right, E is the slice between top and bottom, and S is the slice between front and back.
- x, y and z turn the whole cube, in the same direction as R, U and F.
- r, l, u, d, f and b (small letters) turn two layers together, for example r turns the right face and the middle slice.
Practise reading the letters in the Rubik’s Cube Trainer, or learn a full method in the Beginner Guide. To see turns happen on a 3D cube, try the Rubik’s Cube Solver.