How to solve a 4×4

The reduction method: make the 4×4 look like a 3×3, then solve it with the beginner method you already know. First solve often takes 45–90 minutes. Practise turns on the 4×4 in Cube Lab.

Before you start

A 4×4 has no fixed centres. Each face’s “centre” is a 2×2 block of four pieces that can move. Edges come in pairs (two wings that share the same two colours). Corners are the same as on a 3×3.

• White is still opposite yellow, red opposite orange, green opposite blue — even though the centres move, those colour pairs stay opposite when the cube is solved.
• Build white and yellow centres first (opposites), then the four side centres.
• After centres and edge pairing, ignore the extra slices and solve it like a 3×3.

Two extra cases appear on 4×4. After reduction you may get OLL parity (one edge pair looks flipped) or PLL parity (two edges swapped). Those are real — not a mistake. Algorithms are at the end.

Why reduction

Reduction turns a 4×4 into a familiar 3×3: build 2×2 centres, pair edge wings, then use the beginner (or CFOP) method you already know. You only add parity algorithms for cases that cannot appear on a real 3×3.

Notation

Outer faces use the same letters as 3×3. Inner slices (2R) and wide turns (Rw) are what make 4×4 different.

See the full cube notation reference — including inner/wide layers and Cube Lab controls.

Restore centres after a slice. Pairing uses Uw to bring edges together, then you undo that slice so the centres come back.

Step 1 · Centres

A 2×2 block of the same colour on every face. White opposite yellow, then the four sides.

White, then yellow

Solve white by intuition. Make 1×2 bars (two centre pieces side by side) with inner slices, then join two bars into a 2×2. Hold the finished white centre on the bottom while you build yellow on top so you do not smash white.

The last four centres

Hold white on bottom and yellow on top. The four side centres go around the equator.

Build one side centre (for example green) as two bars, insert them without undoing white/yellow. Then the opposite centre (blue). The last two centres are a commuter: make a bar on the front, insert it, and the last centre solves itself.

If a centre you already solved breaks, you used a slice you did not undo. Reverse the last inner/wide turn and try a different hold.

Step 2 · Edge pairing

24 wing pieces become 12 “dedges” — each 3×3-style edge slot holds two matching colours.

Find two wings that share the same two colours. Put one at front-top (UF). Put its mate in the front-right (FR) or another equator slot so a wide U will bring them together.

1. Turn Uw until the two wings sit next to each other as a matching pair.
2. Replace that pair with any still-unpaired edge so the next slice does not rip the pair apart. A common replace is R U R' (or R' U' R).
3. Undo the slice: Uw' (or Uw2 if you went 180°) so the centres return.

Repeat until every edge slot is a matched pair. You will often have two or three pairs left that need a slightly different hold — flip an unpaired edge into UF with F' U F or R U R' and continue.

Last two pairs. If two pairs are left and a single Uw would swap them wrongly, flip one pair first (R U R') so they can meet, then restore. Do not slice without a plan to undo it.

Step 3 · Solve as a 3×3

Outer turns only. Each 2×2 centre is a 3×3 centre. Each paired edge is a 3×3 edge.

Switch Layer back to Outer. Follow the 3×3 beginner method: white cross, white corners, middle edges, yellow cross, yellow face, then last-layer permutation.

If you already know CFOP, you can use that instead. The extra 4×4 work is already done.

Stop if the last layer looks impossible. A single flipped edge, or two edges that will not permute, is parity — not a broken reduction. Go to the next two steps, then finish the 3×3 last layer.

Step 4 · OLL parity

One edge pair looks flipped. The rest of the last layer can be oriented as usual.

This cannot happen on a 3×3. On 4×4 it is normal after pairing. Hold the flipped pair at the front and run the algorithm, then continue yellow cross / Sune as on 3×3.

In Cube Lab, set Layer to Inner for the 2R / 2L turns, and Outer for U and F. Or type the sequence conceptually: inner-right, outer-up, and so on.

Step 5 · PLL parity

Two opposite edges need to swap. Corners may already be in place.

If two adjacent edges need to swap, use a 3×3 PLL (T-perm, U-perm, …). If two opposite edges are swapped and no 3×3 PLL matches, this is PLL parity. Hold the cube with those two edges at front and back.

Then AUF (turn U) and finish with a normal 3×3 PLL if anything is still off. The cube is solved.

Practice path

• White and yellow centres only until opposite 2×2 blocks are solid.
• Add side centres, then edge pairing — always undo the slice after storing a pair.
• Solve as a 3×3 untimed; when parity appears, use the algorithms on this page instead of forcing 3×3 PLL.
• After reduction feels automatic, try CFOP on the reduced cube.

Stuck?

Centres wrong after pairing: you did not undo a Uw. Restore with the inverse slice, then store the pair again.

A “flipped” centre 2×2 that is the right colour is still solved — 4×4 centres have no rotation to worry about. If two colours are mixed in one 2×2, that centre is not done yet.

If last-layer algorithms from 3×3 scramble the centres, you used an inner or wide turn by accident. Stay on Outer until you hit a parity case.

If you have a physical cube, you can scan all six faces in Cube Lab. That opens Smart Solve, which is a different path from this beginner method.

After this page

A 5×5 is the same reduction idea with a fixed centre and three pieces per edge. Need the 3×3 steps in writing? How to solve a 3×3. The 2×2 is corners only: How to solve a 2×2.