Rules & objective
Fill squares so every row and column matches its number clues.
- Groups appear in the clue’s order and must have at least one empty square between them. Extra empty squares may appear at either end.
- Click a square to cycle through filled, marked empty with X, and unmarked. Only filled squares count toward the clue groups.
- Check picture compares every row and column with its clues. Highlighted clues show matching run patterns, but one matching line alone does not prove the whole placement.
Key terms
- Run
- An uninterrupted group of filled squares.
- Gap
- At least one empty square separating two runs.
- Overlap
- Squares filled in every legal placement of a run within a line.
Difficulty levels
| Level | What changes |
|---|---|
| Easy | 5 × 5 pictures. Follow short row and column clues. |
| Medium | 7 × 7 pictures with longer runs and more gaps. |
| Hard | 9 × 9 pictures. Cross-check more intersecting clues. |
Changing difficulty starts a fresh round. Personal bests are tracked separately.
This version on puzzle free online
Boards grow from 5 × 5 to 7 × 7 and 9 × 9. Next picture cycles through the available puzzles for the chosen tier. Empty squares do not all need X marks to pass the final check.
Common questions
What does a 0 clue mean?
That line contains no filled squares.
Does a clue of 2 1 mean three adjacent filled squares?
No. It means a group of two, at least one empty square, and then a separate group of one.