Four overlapping 9×9 grids · four shared 3×3 corner boxes · 27 puzzles
Level 1/27BeginnerΔ 00:00Mistakes 0/3Best —
How to play Windmill Sudoku
Goal: Fill all four 9×9 grids so every row, column, and 3×3 box contains digits 1-9 exactly once.
Layout: Four grids form a windmill pattern on a 21×21 playfield. The amber 3×3 boxes are shared corners — a digit there counts for both grids that overlap there.
Grid A (teal, top) ← shared TL → Grid D (violet, left), Grid A ← shared TR → Grid B (cyan, right), Grid D ← shared BL → Grid C (green, bottom), Grid B ← shared BR → Grid C.
Tap a cell then tap a digit (1-9) on the palette, or use the keyboard.
Notes mode: toggle pencil marks to track candidates per cell.
Cream = given clue, cyan = your entry, red = conflicting.
Complete all four grids to win. Three mistakes = game over.
Select Level
27 puzzles · progress saved automatically
Level Complete!
Game Over
Three mistakes made. Restart the puzzle or pick a new level.