Fill the 9×9 grid with digits 1–9 so no row or column repeats a number. Each mode adds one more rule: Killer Sudoku — every dashed cage's numbers sum to the target in its corner, with no repeated digit inside a cage. Jigsaw Sudoku — the 9 irregular bold-outlined regions each hold every digit 1–9 exactly once instead of a 3×3 box. Diagonal Sudoku — both corner-to-corner diagonals also hold every digit 1–9 exactly once.

Tap the pencil button or press P to jot candidate notes in a cell instead of placing a final answer.