About Hitori
Hitori is a logic puzzle played on a square of digits. Some digits repeat in their row or column, and your job is to shade squares until each row and column shows every digit at most once among the white squares. Two more rules keep the shading honest: shaded squares never sit side by side, and the white squares stay joined in one shape. Each daily grid has exactly one answer, reached by reasoning alone, and every player gets the same grid, so you can compare times on the leaderboard.
How to play Hitori
- Shade squares until no digit appears twice in any row or column among the white squares.
- Shaded squares never touch side by side (corners are fine), and all the white squares must stay joined in one group, side by side.
- Tap a square to shade it, again to circle it (your note for “this one stays white”), again to clear it. Drag across squares to paint several at once.
- Easy grids are 5 × 5, medium 7 × 7 and hard 9 × 9. Every grid has exactly one answer, found by reasoning alone. Fastest time wins; fewer changes break ties.
Tips & strategy
- Look for a digit between two equal digits, like 4 2 4: the middle one must stay white, because one of the outer 4s is shaded and shaded squares can’t touch.
- Two equal digits side by side, like 5 5, mean one of them stays white, so every other 5 in that row or column must be shaded.
- Every time you shade a square, circle its neighbours: they can never be shaded too.
- Watch the corners and edges. A shading that would wall off a white square or a little group of them from the rest is wrong, so the square must stay white.
Hitori: questions and answers
May I shade a digit that appears only once?
Yes, the rules allow it, but it never helps: the grid has one answer, and in it every white square either touches a shaded one or holds the white squares together.
What are the circles for?
A circle is your own note for a square that stays white. It counts as white and is never checked; the grid is solved as soon as the shaded squares keep every rule.
How is Hitori ranked?
By time, fastest first; fewer changes break ties. Only a member’s first solve of the day counts for the leaderboard.