Academy
XY-WingXY-Wing sudoku technique
The XY-Wing links three cells that each hold exactly two candidates. A pivot with digits XY sees two pincers: one with XZ, one with YZ. Whichever digit the pivot finally takes, X or Y, it pushes one of the pincers to Z. Since some Z is certain, any cell that both pincers can see is barred from holding Z — that digit would contradict whichever pincer becomes Z.
How to find a xy-wing
- List the bi-value cells — cells with exactly two pencil marks. They are the raw material.
- Take one as the pivot (XY) and look for pincers XZ and YZ among the bi-value cells it sees.
- Find every cell that is seen by both pincers at once.
- Strike the shared digit Z from those overlap cells.
The pattern on the grid
A real position — every pencil mark computed, every red candidate a verified elimination. Toggle to see the grid after the move.
XY-Wing 12/5: pivot r4c9, pincers r4c3, r6c8 => r6c3<>5
200700305000000678087000290890307460001800700730002800000594187570000906010670520
Standard 81-character format (0 = empty) — paste it into your solver of choice and verify the move yourself.
Worked example
The pivot r4c9 (12) sees pincers r4c3 and r6c8. Either value of the pivot forces one pincer to 5, so a 5 is guaranteed at one end — and every cell watched by both pincers drops it: r6c3<>5.
When it fails
All three cells must be strictly bi-value, and the pincers must NOT see each other for the classic pattern. A pivot with three candidates makes it an XYZ-Wing with a much smaller elimination zone.
Puzzles that need it
These grids come from rated games on this site — our solver confirmed that xy-wing was part of the shortest solving path for each one.
045900000000710205020003009008301026010000050360805100200100030801057000000009510
600057039278090050000400070500000700360000091002000005020005000050040916480610007
070060230800020007106300900000040800410902063009030000002005401700010006051090020
Every string is the standard 81-character format (0 = empty) — paste it into any solver to verify the rating and the solving path yourself. Want to try one under the clock? Play a free puzzle — no account needed — or create an account to train specific difficulty tiers.