4x4 Trainer

How to solve a 4x4 — Reduction method

The most common beginner approach is Reduction: turn the 4x4 into a "3x3" by solving the centres and pairing the edges, then finish with normal 3x3 algorithms. The 4x4 has no fixed centres, so you choose where each colour goes — which is also why parity cases can appear at the end.

1. Solve the centres (1 of 6).

   Build a 2x2 block of one colour on any face using inner-slice moves (r, l, u). Start with white or yellow so you can keep an eye on it.

2. Solve the opposite centre.

   Build the opposite-colour centre on the back face. Use slice moves that do not disturb the first centre — keep it on top and only touch the bottom two layers.

3. Solve the remaining four centres.

   Place the last four centres in the correct colour scheme (white opposite yellow, red opposite orange, blue opposite green, with red–green–white arranged clockwise around their shared corner). The trick: solve two adjacent centres at the same time so the last two are forced.

4. Pair the edges.

   Each 3x3 edge becomes two "wings" on a 4x4. Hold two matching wings on the front-left and front-right, then run U' R U (or similar) to join them into a single edge while replacing it with an unsolved pair. This is called 3-2-3 edge pairingor slice-and-flip.

5. Fix a bad edge if needed.

   If a pair has one flipped wing, hold it front-right and use the edge-flip algorithm below to repair it without breaking your other pairs.

6. Solve as a 3x3.

   Treat each paired edge and each centre as a single sticker. Use only outer-layer moves (R, U,F, …) so you do not break the reduction. Solve cross, F2L, OLL, and PLL exactly like a 3x3.

7. Handle parity.

   OLL parity appears when a single last-layer edge looks flipped after orienting — impossible on a 3x3. PLL parity appears when two adjacent last-layer edges need to swap. Apply the matching algorithm from the cards below, then finish the solve normally.