PLL Recognition: Know the Case From Just Two Sides

This post shows you how to do PLL recognition using only the two sides you can see while holding the cube, with no need to turn the top face around to look for clues. You get four lookup tables covering all 21 cases, and every situation in the tables has its own picture. Every rule in this post has been checked on the EasyRubic simulator against all 288 ways the top layer can be arranged after OLL.

Find your case fast

Look at your cube from above and tap the picture that matches it to see how to solve it. Grey cells are stickers you can ignore.

Case 1
R2U2RU2R2U2R2U2RU2R2
1. You start with (input)
3. After the formula
See it in the post →
Case 2
RB′R′FRBR′F′RBR′FRB′R′F′
1. You start with (input)
3. After the formula
See it in the post →
Case 3
URUR′U′R′FR2U′R′U′RUR′F′U′
1. You start with (input)
3. After the formula
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Case 4
U2RU′RURURU′R′U′R2U2
1. You start with (input)
3. After the formula
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Case 5
U2R2URUR′U′R′U′R′UR′U2
1. You start with (input)
3. After the formula
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Case 6
U′RU′RURURU′R′U′R2U
1. You start with (input)
3. After the formula
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Case 7
U′R2URUR′U′R′U′R′UR′U
1. You start with (input)
3. After the formula
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Case 8
R2U2RU2R2U2R2U2RU2R2
1. You start with (input)
3. After the formula
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Case 9
RU′RURURU′R′U′R2
1. You start with (input)
3. After the formula
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Case 10
UR2URUR′U′R′U′R′UR′U′
1. You start with (input)
3. After the formula
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Case 11
U′R′U′RU′RURU′R′URUR2U′R′U′
1. You start with (input)
3. After the formula
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Case 12
R′U′RU′RURU′R′URUR2U′R′U2
1. You start with (input)
3. After the formula
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Case 13
URU′RURURU′R′U′R2U′
1. You start with (input)
3. After the formula
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Case 14
R2URUR′U′R′U′R′UR′
1. You start with (input)
3. After the formula
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Case 15
FRU′R′U′RUR′F′RUR′U′R′FRF′
1. You start with (input)
3. After the formula
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Case 16
UR′UR′U′B′R′B2U′B′UB′RBRU′
1. You start with (input)
3. After the formula
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Case 17
RUR′URUR′F′RUR′U′R′FR2U′R′U2RU′R′
1. You start with (input)
3. After the formula
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Case 18
R′URU′R′F′U′FRUR′FR′F′RU′R
1. You start with (input)
3. After the formula
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Case 19
R′UR′U′B′R′B2U′B′UB′RBR
1. You start with (input)
3. After the formula
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Case 20
U2R′UR′U′B′R′B2U′B′UB′RBR
1. You start with (input)
3. After the formula
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Case 21
U′FRU′R′U′RUR′F′RUR′U′R′FRF′
1. You start with (input)
3. After the formula
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Case 22
U′FRU′R′U′RUR′F′RUR′U′R′FRF′U′
1. You start with (input)
3. After the formula
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Case 23
U′R′UR′U′B′R′B2U′B′UB′RBR
1. You start with (input)
3. After the formula
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Case 24
U2FRU′R′U′RUR′F′RUR′U′R′FRF′U2
1. You start with (input)
3. After the formula
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Case 25
RB′R′FRBR′F′RBR′FRB′R′F′
1. You start with (input)
3. After the formula
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Case 26
R′UL′U2RU′R′U2RLU′
1. You start with (input)
3. After the formula
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Case 27
U2RUR′F′RUR′U′R′FR2U′R′
1. You start with (input)
3. After the formula
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Case 28
URUR′F′RUR′U′R′FR2U′R′U2
1. You start with (input)
3. After the formula
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Case 29
UR′UL′U2RU′R′U2RLU
1. You start with (input)
3. After the formula
See it in the post →
Case 30
UR′U′F′RUR′U′R′FR2U′R′U′RUR′URU′
1. You start with (input)
3. After the formula
See it in the post →
Case 31
U2R′U′F′RUR′U′R′FR2U′R′U′RUR′URU
1. You start with (input)
3. After the formula
See it in the post →
Case 32
URUR′U′R′FR2U′R′U′RUR′F′U′
1. You start with (input)
3. After the formula
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Case 33
U2RUR′U′R′FR2U′R′U′RUR′F′U
1. You start with (input)
3. After the formula
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Case 34
URU′R′U′RURDR′U′RD′R′U2R′U2
1. You start with (input)
3. After the formula
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Case 35
U2R2FRURU′R′F′RU2R′U2RU2
1. You start with (input)
3. After the formula
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Case 36
U2R′FR′B2RF′R′B2R2U
1. You start with (input)
3. After the formula
See it in the post →
Case 37
R2B2RFR′B2RF′R
1. You start with (input)
3. After the formula
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Case 38
UR2UR′UR′U′RU′R2U′DR′URD′U′
1. You start with (input)
3. After the formula
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Case 39
U2R2U′RU′RUR′UR2UD′RU′R′DU
1. You start with (input)
3. After the formula
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Case 40
URUR′U′DR2U′RU′R′UR′UR2D′U′
1. You start with (input)
3. After the formula
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Case 41
U2R′U′RUD′R2UR′URU′RU′R2DU
1. You start with (input)
3. After the formula
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Case 42
UR′U′RUD′R2UR′URU′RU′R2DU′
1. You start with (input)
3. After the formula
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Case 43
U2RUR′U′DR2U′RU′R′UR′UR2D′U
1. You start with (input)
3. After the formula
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Case 44
UR2FRURU′R′F′RU2R′U2R
1. You start with (input)
3. After the formula
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Case 45
U2RU′R′U′RURDR′U′RD′R′U2R′
1. You start with (input)
3. After the formula
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Case 46
UR2U′RU′RUR′UR2UD′RU′R′DU′
1. You start with (input)
3. After the formula
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Case 47
U2R2UR′UR′U′RU′R2U′DR′URD′U
1. You start with (input)
3. After the formula
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Case 48
U′R2B2RFR′B2RF′RU2
1. You start with (input)
3. After the formula
See it in the post →
Case 49
U′R′FR′B2RF′R′B2R2U′
1. You start with (input)
3. After the formula
See it in the post →
Case 50
U2R′UL′U2RU′R′U2RLU2
1. You start with (input)
3. After the formula
See it in the post →
Case 51
U′R′UL′U2RU′R′U2RL
1. You start with (input)
3. After the formula
See it in the post →
Case 52
U′RUR′F′RUR′U′R′FR2U′R′U
1. You start with (input)
3. After the formula
See it in the post →
Case 53
RUR′F′RUR′U′R′FR2U′R′U′
1. You start with (input)
3. After the formula
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Case 54
UR2B2RFR′B2RF′RU
1. You start with (input)
3. After the formula
See it in the post →
Case 55
UR′FR′B2RF′R′B2R2U2
1. You start with (input)
3. After the formula
See it in the post →
Case 56
U′R2FRURU′R′F′RU2R′U2RU′
1. You start with (input)
3. After the formula
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Case 57
RU′R′U′RURDR′U′RD′R′U2R′U′
1. You start with (input)
3. After the formula
See it in the post →
Case 58
U′RUR′U′R′FR2U′R′U′RUR′F′U2
1. You start with (input)
3. After the formula
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Case 59
RUR′U′R′FR2U′R′U′RUR′F′
1. You start with (input)
3. After the formula
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Case 60
U′R2U′RU′RUR′UR2UD′RU′R′DU2
1. You start with (input)
3. After the formula
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Case 61
R2UR′UR′U′RU′R2U′DR′URD′
1. You start with (input)
3. After the formula
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Case 62
U′R′U′RUD′R2UR′URU′RU′R2DU2
1. You start with (input)
3. After the formula
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Case 63
RUR′U′DR2U′RU′R′UR′UR2D′
1. You start with (input)
3. After the formula
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Case 64
U′RUR′U′DR2U′RU′R′UR′UR2D′U2
1. You start with (input)
3. After the formula
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Case 65
R′U′RUD′R2UR′URU′RU′R2D
1. You start with (input)
3. After the formula
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Case 66
R′FR′B2RF′R′B2R2
1. You start with (input)
3. After the formula
See it in the post →
Case 67
U2R2B2RFR′B2RF′RU′
1. You start with (input)
3. After the formula
See it in the post →
Case 68
U′R′U′F′RUR′U′R′FR2U′R′U′RUR′URU2
1. You start with (input)
3. After the formula
See it in the post →
Case 69
R′U′F′RUR′U′R′FR2U′R′U′RUR′UR
1. You start with (input)
3. After the formula
See it in the post →
Case 70
U′RU′R′U′RURDR′U′RD′R′U2R′U
1. You start with (input)
3. After the formula
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Case 71
R2FRURU′R′F′RU2R′U2RU
1. You start with (input)
3. After the formula
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Case 72
U′R2UR′UR′U′RU′R2U′DR′URD′U2
1. You start with (input)
3. After the formula
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Case 73
R2U′RU′RUR′UR2UD′RU′R′D
1. You start with (input)
3. After the formula
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This post is only about how to look. The algorithm for each case is in 21 PLL algorithms; if you are still using 2-look PLL, see 2-look PLL first.

Why are two sides enough?

When you finish OLL, you hold the cube and can see the top row of two side faces: the front and the right. That's 6 stickers. Sarah Strong, who writes Sarah's Cubing Site, says these 6 stickers are always enough to tell which PLL case you have (Sarah's Cubing Site).

We tried this on the simulator: we took all 288 top-layer arrangements, wrote down the 6 visible stickers, and no two cases gave the same picture.

The benefit is clear: you don't have to turn U once or twice to find headlights before you start the algorithm. An article by Cubelelo estimates that this way of looking saves about 0.5 to 1 second per solve, depending on your current level (Cubelelo).

How to read the pictures

Each picture has two cubes: on the left is the case you have, on the right is the cube after the algorithm. Only the top layer is coloured in.
In the pictures, the face on the left of the image is the front face, and the face on the right of the image is the right face. The two faces meet at the middle corner: the corner piece that has one sticker on each face.
When this post says "left" and "right", it means the left and right of the two sides you can see, exactly as in the pictures.
Each picture is drawn with an algorithm that has an extra U at the start or end, to put the case at that exact angle. You don't need to know these algorithms; just look at the cube on the left.

Five things to look for

Headlights: the two corner stickers on the same side are the same colour.
Pair: a corner sticker and the edge sticker next to it are the same colour. An inner pair sits right next to the middle corner, an outer pair sits at the far end.
Full bar: all three stickers on one side are the same colour.
Opposite colours: two colours that sit on opposite faces of a solved cube. On a cube with the standard colour scheme: green is opposite blue, and red is opposite orange. Two different colours that are not opposite are called adjacent colours.
Number of colours: count how many different colours there are in the 6 stickers. For PLL, this number is always 2, 3 or 4.

You need to know the opposite colour pairs by heart to recognise cases quickly. If you are not sure yet, pick up a solved cube and look at two opposite faces a few times.

Step 1: look at the four corner stickers

Ignore the edge stickers. Only look at the two corner stickers on the left side and the two corner stickers on the right side. Sorting cases by their corners like this is the first step in Sarah Strong's guide; below is how we have laid it out:

What you see	Group	Cases
Headlights on both sides	Corners already in place, only edges swap	Ua, Ub, H, Z
No headlights, each side has two corners in opposite colours	Two diagonal corners need to swap	Y, V, Na, Nb, E
Headlights on exactly one side	Two neighbouring corners need to swap	T, F, Ja, Jb, Ra, Rb, Aa, Ab, Ga, Gb, Gc, Gd
No headlights, only one side has two corners in opposite colours	Two neighbouring corners need to swap (headlights at the back)	same as the row above

Three examples, one picture for each group:

H-perm: headlights on both sides.

See it in 3D, before and after

You start with (input)
After the formula

E-perm: the left side has red and orange on its two corners, the right side has blue and green. Both sides have opposite colours.

See it in 3D, before and after

You start with (input)
After the formula

T-perm: green headlights on the left side, none on the right side.

See it in 3D, before and after

You start with (input)
After the formula

The last two rows of the table are the same group. When the headlights are on the back or left face of the cube (a face you can't see), you won't see any headlights, but the side facing them will have two corners in opposite colours.

Group 1: headlights on both sides (Ua, Ub, H, Z)

All four corners are already in place. Now look at the two edge stickers, the middle sticker on each side. Ask yourself: is that edge sticker the opposite colour of the headlights on its own side?

What you see	Case
Full bar on both sides	No PLL needed, just turn U
Full bar on the left, right edge is an adjacent colour	Ua
Full bar on the left, right edge is the opposite colour	Ub
Full bar on the right, left edge is the opposite colour	Ua
Full bar on the right, left edge is an adjacent colour	Ub
Both edges are the opposite colour	H
Only the right edge is the opposite colour	Ua
Only the left edge is the opposite colour	Ub
Neither edge is the opposite colour, 2 or 4 colours	Z
Neither edge is the opposite colour, 3 colours, left edge is the colour of the right headlights	Ua
Neither edge is the opposite colour, 3 colours, right edge is the colour of the left headlights	Ub

With a full bar

Ua-perm: full bar on the left, the right edge is an adjacent colour to its headlights.

See it in 3D, before and after

You start with (input)
After the formula

Ub-perm: full bar on the left, the right edge is the opposite colour.

See it in 3D, before and after

You start with (input)
After the formula

Ua-perm: full bar on the right, the left edge is the opposite colour.

See it in 3D, before and after

You start with (input)
After the formula

Ub-perm: full bar on the right, the left edge is an adjacent colour.

See it in 3D, before and after

You start with (input)
After the formula

Memory tip: full bar on one side, the edge on the other side is the opposite colour. If the full bar is on the left, it's Ub; if it's on the right, it's Ua.

Without a full bar

H-perm: both edges are the opposite colour of their headlights.

See it in 3D, before and after

You start with (input)
After the formula

Ua-perm: only the right edge is the opposite colour.

See it in 3D, before and after

You start with (input)
After the formula

Ub-perm: only the left edge is the opposite colour.

See it in 3D, before and after

You start with (input)
After the formula

Z-perm: neither edge is the opposite colour, and all 6 stickers use just 2 colours, alternating like a chessboard.

See it in 3D, before and after

You start with (input)
After the formula

Z-perm: again neither edge is the opposite colour, but all 4 colours show up.

See it in 3D, before and after

You start with (input)
After the formula

Ua-perm: 3 colours, the left edge is exactly the colour of the right headlights.

See it in 3D, before and after

You start with (input)
After the formula

Ub-perm: 3 colours, the right edge is exactly the colour of the left headlights.

See it in 3D, before and after

You start with (input)
After the formula

Group 2: two diagonal corners (Y, V, Na, Nb, E)

There are no headlights, and each side has two corners in opposite colours. Now look for pairs.

What you see	Case
Two pairs, both outer	Y
Two pairs, both inner (meeting at the middle corner)	V
Two pairs, both at the right end of their own side	Na
Two pairs, both at the left end of their own side	Nb
One outer pair	V
One inner pair	Y
No pairs, the four middle stickers alternate between two colours	V
No pairs, the two leftmost stickers repeat as the two rightmost stickers	Y
No pairs, none of the above	E

Two pairs

Y-perm: two outer pairs.

See it in 3D, before and after

You start with (input)
After the formula

V-perm: two inner pairs, both touching the middle corner.

See it in 3D, before and after

You start with (input)
After the formula

Na-perm: the left pair sits right next to the middle corner, the right pair sits at the far end. Both are at the right end of their own side.

See it in 3D, before and after

You start with (input)
After the formula

Nb-perm: the other way round, both pairs are at the left end of their own side.

See it in 3D, before and after

You start with (input)
After the formula

One pair

V-perm: one outer pair, on the left side.

See it in 3D, before and after

You start with (input)
After the formula

V-perm: one outer pair, on the right side.

See it in 3D, before and after

You start with (input)
After the formula

Y-perm: one inner pair, on the left side.

See it in 3D, before and after

You start with (input)
After the formula

Y-perm: one inner pair, again on the left side but in a different colour.

See it in 3D, before and after

You start with (input)
After the formula

Memory tip: Y and V swap roles when you only see one pair. Two outer pairs means Y, but one outer pair means V.

No pairs

V-perm: the four middle stickers (left edge, the middle corner on both sides, right edge) alternate between two colours.

See it in 3D, before and after

You start with (input)
After the formula

Y-perm: the leftmost corner and edge have the same two colours, in the same order, as the rightmost edge and corner.

See it in 3D, before and after

You start with (input)
After the formula

E-perm: no pairs, and none of the patterns above. The E-perm is the "nothing special" case.

See it in 3D, before and after

You start with (input)
After the formula

Group 3: headlights on one side

This is the group with the most cases. We'll call the side with headlights the headlight side, and the other one the other side. The table has two columns because the answer depends on whether the headlight side is on the left or the right.

What you see	Headlights on the left	Headlights on the right
Headlight side is a full bar, other side has an inner pair	Ja	Jb
Headlight side is a full bar, other side has an outer pair	Jb	Ja
Headlight side is a full bar, other side has no pair	F	F
Other side has an inner pair, edge between the headlights is the opposite colour	T	T
Other side has an inner pair, edge between the headlights is an adjacent colour	Ra	Rb
Other side has an outer pair, 3 colours	Aa	Ab
Other side has an outer pair, 4 colours	Ga	Gc
No pair, edge between the headlights is the opposite colour, 3 colours	Gd	Gb
No pair, edge between the headlights is the opposite colour, 4 colours	Gb	Gd
No pair, edge between the headlights is an adjacent colour, 3 colours	Rb	Ra
No pair, edge between the headlights is an adjacent colour, 4 colours, middle corner on the other side is the same colour as that edge	Gc	Ga
No pair, edge between the headlights is an adjacent colour, 4 colours, anything else	Ab	Aa

Below, each row of the table has two pictures: headlights on the left first, then headlights on the right.

Headlight side is a full bar: J and F

Ja-perm: full bar on the left, inner pair on the right.

See it in 3D, before and after

You start with (input)
After the formula

Jb-perm: full bar on the right, inner pair on the left.

See it in 3D, before and after

You start with (input)
After the formula

Jb-perm: full bar on the left, outer pair on the right.

See it in 3D, before and after

You start with (input)
After the formula

Ja-perm: full bar on the right, outer pair on the left.

See it in 3D, before and after

You start with (input)
After the formula

Memory tip for J: look at which end of its own side the pair is on. Pair at the left end is Ja, at the right end is Jb.

F-perm: full bar on the left, no pair on the right side.

See it in 3D, before and after

You start with (input)
After the formula

F-perm: full bar on the right, no pair on the left side.

See it in 3D, before and after

You start with (input)
After the formula

Inner pair: T and R

T-perm: headlights on the left, the edge between the headlights is the opposite colour, inner pair on the right.

See it in 3D, before and after

You start with (input)
After the formula

T-perm: headlights on the right, same pattern.

See it in 3D, before and after

You start with (input)
After the formula

Ra-perm: headlights on the left, the edge between the headlights is an adjacent colour, inner pair on the right.

See it in 3D, before and after

You start with (input)
After the formula

Rb-perm: headlights on the right, the edge between the headlights is an adjacent colour, inner pair on the left.

See it in 3D, before and after

You start with (input)
After the formula

Outer pair: A and G

Aa-perm: headlights on the left, outer pair on the right, only 3 colours.

See it in 3D, before and after

You start with (input)
After the formula

Ab-perm: headlights on the right, outer pair on the left, only 3 colours.

See it in 3D, before and after

You start with (input)
After the formula

Ga-perm: headlights on the left, outer pair on the right, all 4 colours.

See it in 3D, before and after

You start with (input)
After the formula

Gc-perm: headlights on the right, outer pair on the left, all 4 colours.

See it in 3D, before and after

You start with (input)
After the formula

No pair, edge between the headlights is the opposite colour: Gb and Gd

Gd-perm: headlights on the left, 3 colours.

See it in 3D, before and after

You start with (input)
After the formula

Gb-perm: headlights on the right, 3 colours.

See it in 3D, before and after

You start with (input)
After the formula

Gb-perm: headlights on the left, 4 colours.

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You start with (input)
After the formula

Gd-perm: headlights on the right, 4 colours.

See it in 3D, before and after

You start with (input)
After the formula

No pair, edge between the headlights is an adjacent colour: R, G and A

Rb-perm: headlights on the left, 3 colours.

See it in 3D, before and after

You start with (input)
After the formula

Ra-perm: headlights on the right, 3 colours.

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You start with (input)
After the formula

Gc-perm: headlights on the left, 4 colours, and the middle corner sticker on the right side is the same colour as the edge between the headlights. The first four stickers alternate between two colours.

See it in 3D, before and after

You start with (input)
After the formula

Ga-perm: headlights on the right, 4 colours, the middle corner sticker on the left side is the same colour as the edge between the headlights.

See it in 3D, before and after

You start with (input)
After the formula

Ab-perm: headlights on the left, 4 colours, without that alternating pattern.

See it in 3D, before and after

You start with (input)
After the formula

Aa-perm: headlights on the right, 4 colours, without that alternating pattern.

See it in 3D, before and after

You start with (input)
After the formula

Group 4: no headlights, one side has two corners in opposite colours

The headlights are on a face you can't see. We'll call the side with two opposite-coloured corners the diagonal side, and the other one the other side.

What you see	Diagonal side on the left	Diagonal side on the right
Two pairs, both at the left end of their own side	Ja	Ja
Two pairs, both at the right end of their own side	Jb	Jb
Two inner pairs, meeting at the middle corner	Ab	Aa
Only one pair, outer, on the other side, 3 colours	Rb	Ra
Only one pair, outer, on the other side, 4 colours	T	T
Only one pair, inner, on the other side	Gc	Ga
Only one pair, inner, on the diagonal side	Gb	Gd
Only one pair, outer, on the diagonal side, 3 colours	Gd	Gb
Only one pair, outer, on the diagonal side, 4 colours	Aa	Ab
No pair, 3 colours	F	F
No pair, 4 colours, edge on the diagonal side is the same colour as the middle corner on the other side	Ra	Rb
No pair, 4 colours, anything else	Ga	Gc

Two pairs: J and A

Ja-perm: diagonal side on the left, both pairs at the left end.

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You start with (input)
After the formula

Ja-perm: diagonal side on the right, both pairs at the left end.

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You start with (input)
After the formula

Jb-perm: diagonal side on the left, both pairs at the right end.

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You start with (input)
After the formula

Jb-perm: diagonal side on the right, both pairs at the right end.

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You start with (input)
After the formula

Ab-perm: diagonal side on the left, two inner pairs.

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You start with (input)
After the formula

Aa-perm: diagonal side on the right, two inner pairs.

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You start with (input)
After the formula

One pair on the other side: R, T and G

Rb-perm: diagonal side on the left, outer pair on the right, 3 colours.

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You start with (input)
After the formula

Ra-perm: diagonal side on the right, outer pair on the left, 3 colours.

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You start with (input)
After the formula

T-perm: diagonal side on the left, outer pair on the right, 4 colours.

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You start with (input)
After the formula

T-perm: diagonal side on the right, outer pair on the left, 4 colours.

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You start with (input)
After the formula

Gc-perm: diagonal side on the left, inner pair on the right.

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You start with (input)
After the formula

Ga-perm: diagonal side on the right, inner pair on the left.

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You start with (input)
After the formula

One pair on the diagonal side: G and A

Gb-perm: diagonal side on the left, with an inner pair on that same side.

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You start with (input)
After the formula

Gd-perm: diagonal side on the right, with an inner pair on that same side.

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You start with (input)
After the formula

Gd-perm: diagonal side on the left, outer pair, 3 colours.

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You start with (input)
After the formula

Gb-perm: diagonal side on the right, outer pair, 3 colours.

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You start with (input)
After the formula

Aa-perm: diagonal side on the left, outer pair, 4 colours.

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You start with (input)
After the formula

Ab-perm: diagonal side on the right, outer pair, 4 colours.

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You start with (input)
After the formula

No pairs: F, R and G

F-perm: diagonal side on the left, 3 colours.

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You start with (input)
After the formula

F-perm: diagonal side on the right, 3 colours.

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You start with (input)
After the formula

Ra-perm: diagonal side on the left, 4 colours, the left edge is the same colour as the middle corner on the right side.

See it in 3D, before and after

You start with (input)
After the formula

Rb-perm: diagonal side on the right, 4 colours, the right edge is the same colour as the middle corner on the left side.

See it in 3D, before and after

You start with (input)
After the formula

Ga-perm: diagonal side on the left, 4 colours, without that pattern.

See it in 3D, before and after

You start with (input)
After the formula

Gc-perm: diagonal side on the right, 4 colours, without that pattern.

See it in 3D, before and after

You start with (input)
After the formula

How to practise PLL recognition

Don't try to take in all four tables at once. Here is the order we suggest:

Step 1 (the four corner stickers): practise until you can name the group the moment you look. This is the step you will use most.
Group 1: only 4 cases, and you already know them from 2-look PLL.
Group 2: Y and V come up often; N and E are rare.
Groups 3 and 4: go letter by letter: J and F first, then T and R, and finally A and G.

A simple way to practise on a real cube:

Starting from a solved cube, do a PLL algorithm backwards (read it from the end to the start, turning every move the other way), then turn U a few random times.
Look at the front and right sides and say the name of the case. Only then turn the cube to check.
Once you are getting it right most of the time, do full solves and time them on the 3x3 timer. Now notice whether you have to stop and think at PLL.

If you are not sure about a situation, just turn U once and look again. Recognising the case correctly matters more than recognising it fast; the speed comes later.

Common mistakes

Mixing up adjacent and opposite colours. Red and orange are easy to confuse under warm yellow light. Practise under white light.
Forgetting that the middle corner has two stickers. The sticker on the left side and the sticker on the right side of the middle corner are usually different colours, and both of them matter.
Counting the colours wrong. Only count the 6 stickers in the top row of the two sides, not the yellow top face.
Mixing up left and right when the cube is tilted. Always hold the cube so the front and right faces are level with your eyes, as in the pictures.

What's next

Other parts of the CFOP series: how to do the cross, intuitive F2L, the 41 F2L cases, 57 OLL algorithms, 21 PLL algorithms, and the overall roadmap in What is CFOP.

With the EasyRubic app, you can scan your real cube with the camera and see the solution step by step on a 3D cube. Get EasyRubic to practise PLL recognition on your own cube.

Video

Want to see it in motion? The short video below from the Việt Roux channel on YouTube (in Vietnamese) shows more of what this post covers. The video belongs to that channel and is embedded straight from YouTube.

Cách cải thiện thành tích OLL và PLL | Việt RouxVideo · Việt Roux · YouTube

Sources

Frequently asked questions

Is two-sided PLL recognition hard?

At first it can be slower than turning U to look around, because you have to remember the tables. Start with the step where you look at the four corner stickers, then add one group at a time; once you are used to it, you won't need to turn U to look around any more.

What are headlights in PLL?

Headlights are two corner stickers of the same colour on one side face. They tell you those two corners are already in the right place relative to each other.

Are there any cases you can't recognise from two sides?

No. The 6 stickers in the top row of the two sides are always enough to tell every case apart. We checked this against all 288 top-layer arrangements.

I don't know the opposite colours yet. Can I still use this post?

Yes, but get them down first: on a cube with the standard colour scheme, white is opposite yellow, green is opposite blue, and red is opposite orange. Almost every row in the tables depends on this.

When should I start using two-sided recognition?

Once you know most of the 21 PLL algorithms. If you are still using 2-look PLL, step 1 of this post (looking at the four corner stickers) still tells you straight away which kind of corner swap you need.

EasyRubic Editorial

Friendly notes for anyone who wants to solve their first Rubik’s Cube.

Ready for your first turn?

Go from reading notation to each step of a solved cube.

Start with step 0

Learn the 3x3 step by step · 3x3 online timer

Find your case fast

Why are two sides enough?

How to read the pictures

Five things to look for

Step 1: look at the four corner stickers

Group 1: headlights on both sides (Ua, Ub, H, Z)

With a full bar

Without a full bar

Group 2: two diagonal corners (Y, V, Na, Nb, E)

Two pairs

One pair

No pairs

Group 3: headlights on one side

Headlight side is a full bar: J and F

Inner pair: T and R

Outer pair: A and G

No pair, edge between the headlights is the opposite colour: Gb and Gd

No pair, edge between the headlights is an adjacent colour: R, G and A

Group 4: no headlights, one side has two corners in opposite colours

Two pairs: J and A

One pair on the other side: R, T and G

One pair on the diagonal side: G and A

No pairs: F, R and G

How to practise PLL recognition

Common mistakes

What's next

Video

Sources

Frequently asked questions

EasyRubic Editorial

Ready for your first turn?

Another angle.

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