How to Solve the Rubik's Cube/CF

< How to Solve the Rubik's Cube

There are some things that are very important to know:

Now that that's out of the way, let's begin!

Notation

While many notations exist, this seems to be pretty much the most common and standardized.

F: Front face
B: Back face
L: Left face
R: Right face
U: Up face
D: Down face


If a side's letter is shown unaltered (e.g. R), it is rotated clockwise (as seen face-on). If it is followed by an apostrophe, it means counterclockwise (e.g. L'). Finally, if it is followed by a 2, turn it twice i.e. 180 degrees (e.g. U2).

While performing one of the move sequences during a step, don't rotate the cube. Only rotate the cube (thus changing the sides referred to by the letters) when instructed to. If when you begin a step the end condition is already fulfilled, simply move on to the following step.

Step 1: Up face cross

Select a colour to begin with, e.g. white. Rotate the cube so that this is the up (U) face. Now note the color on the front (F) side. Find the edge cubie with the up colour and the front colour and twist the cube to place it on the edge connecting the front and up sides. Ideally, it will be correctly oriented, but if the colours are swapped to the wrong sides perform the following sequence once:

F U' R U

This will flip the cubie so that the colours are on the correct sides. Next, rotate the cube 90 degrees so that the front side is now the left (L) side, and the right (R) side becomes the front. It must be rotated this way and not the other. Now repeat the procedure for this side. If the up or left (i.e. previously done) sides are rotated to move the needed edge cubie, rotate them back immediately after 'extracting' the cubie so as to preserve your efforts thus far. Once the up face has a cross on it (regardless of whether any corners are correctly coloured as well), this step is complete. Go onto the next step.

Step 2: Up face corners

Find one of the corner cubies on the bottom layer that has one face as the up colour. If, for example, its colours are white (as the up colour), red and green, turn the bottom layer until it is a corner on both the red and green faces, i.e. it is directly below the place where it should be. Perform the following sequence either once, three times or five times until the corner is in the right place and orientation:

R' D' R D

If the sequence puts another corner cubie in the relevant upper corner that is not the correct colours, do not stop the sequence. Keep going until the correct cubie is placed. If there is a corner cubie in the top layer that is either the or incorrectly oriented, perform the same sequence once to move it to the bottom layer. From there, repeat the step as above. Once the up face is completely solved, flip the cube over completely, so that the up face is on the bottom and the down (D) face is on the top, and proceed to the next step.

Step 3: Middle layer edges

At the start of this step, you should have an upside-down 'T' shape of four correctly placed cubies on each of the side faces and the down face should be solved. Find an edge cubie on the top layer that has two colours on it that are not that of the up face: this cubie will now be moved to the middle layer. Rotate the top layer until the side (not top) face of this cubie extends one of the short T's; the cubie's top face now match the colour of one of the adjacent side faces. Rotate the whole cube so that the two faces whose colours match the cubie are F and R: the big T is now on either F or R. If the big T is on F (and the top face matches R), perform:

U R U' R' U' F' U F

If, on the other hand, the big T is on the R face, perform:

U' F' U F U R U' R'

This will place the edge cubie, correctly positioned and oriented, into the middle layer.

Repeat the step for the other three edge cubies which need to be in the middle layer. If one of them is already in the middle layer, but is not correct, hold the cube so that it is on the F and R face and perform either of the sequences once. It will then be on the top layer, and you can perform the step normally.

Once you have a 2x3 solved block on the bottom part of each side face, proceed to step four.

Step 4: Up face cross

Note that this is the up face now i.e. the face that is opposite to the original up face that you chose for step one. Turn the top layer until one of the following patterns is visible:

Once you locate one of these, perform the following sequence to advance the pattern through the list:

F R U R' U' F'

The result of this is that the first pattern becomes the second, the second becomes the third, and the third becomes the solved cross, completing the step. If necessary, repeat the initial part of the step between sequences to find the pattern if it is not visible (sometimes it isn't).

Step 5: Top layer edges

Similarly to step one, you must now have the up face cross with the edge cubeis on the correct side faces as well. The method this time is different: turn the top layer until at least one of the edge cubies is correct. If the colour to its right needs doing, have the just-done one on the F face and perform the following sequence either once or twice until the edge cubie on the R face is done:

R U R' U R U2 R'

Now check the B and L faces. If they also need doing, have the first one (F) on the R face and the L face now on F. Perform the sequence once, and follow it with:

U

This will complete the step.

Step 6: Top layer corners (placement)

This step places the corners correctly. Don't worry about orientating them yet. Find a corner piece that's in the right place (regardless of orientation). Rotate the cube so that it is the U/F/R corner and perform:

U R U' L' U R' U' L

If the corners are still not all correctly placed, repeat the sequence once again. If none of the corners are correct, just perform the sequence once on any of the four top corners, then find one that has become correctly placed. Once the corners are in the right places, move on to the final step.

Step 7: Top layer corners (orientation)

Choose one of the unsolved top corners and treat it exactly as you did with step two, although it will require an even number of iterations of the sequence this time, either twice or four times:

R' D' R D

After this, rotate the top layer (not the whole cube) to position another unsolved corner where the solved one just was. Repeat the sequence, then do the next corner. After solving the last corner, only one more twist (which should be obvious) remains. Congratulations, you've solved the Rubik's Cube!

Another possible combination for solving the orientation of the corner pieces is to flip two of them at once without affecting the rest of the cube. Position the two corner pieces that will be flipped in the UFR and URB positions and use the combination...

L U L' U L U2 L' R' U' R U' R' U2 R

to flip the corners. You may need to flip a corner that is already correct if you have two diagonal corners incorrect or flip a corner twice. Notice that the pattern is reversed halfway through, this should make it easier to remember.

How to solve the 2x2x2 (Mini/Pocket Cube)

If you know how to solve the 3x3x3 cube (see above), solving the 2x2x2 can be achieved by treating the cube as a 3x3x3 in which the centre and edge cubes are in a permanent solved state regardless of what moves you make. In other words, the solution consists of only the corner-solving steps of the 3x3x3 solution. The important thing is simply to remember which side is which (since you can't see the middle layers, because they aren't actually there), although this shouldn't be too difficult.

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