Nonogram
PuzzleDesktop: left-click to fill, right-click to mark. Mobile: tap a cell, switch modes above.
How to Play
Goal: Reveal the hidden picture by filling the correct cells in the grid.
Clues: The numbers on the left tell you the runs of filled cells in each row. The numbers on top do the same for each column. A clue of "3 1" means a run of three filled cells, then a gap, then one filled cell, in that order.
Controls: Left-click a cell to fill it, right-click to mark it with an X for "definitely empty". On mobile, use the Fill and Mark X buttons to choose your mode, then tap cells. X marks are just notes, they never count toward solving.
Winning: Fill every cell that belongs to the picture and leave the rest empty. The puzzle solves itself the moment your filled cells match the solution.
About Nonogram
Nonograms, also called Picross, Griddlers or picture crosswords, were born in Japan in the late 1980s, credited jointly to designer Non Ishida and puzzler Tetsuya Nishio. The name honors Ishida ('Non-o-gram'), and Nintendo's Picross series later carried the format to the world. Numbers on each row and column describe runs of filled cells; solve them all and a pixel picture appears.
A nonogram is logic you can see. Each clue like '4 2' means a block of four filled cells, at least one gap, then a block of two, in that order. Cross-referencing row constraints against column constraints, filling certain cells and X-ing impossible ones, gradually forces the image out of the grid. Well-made puzzles never require guessing, only patience.
Nonogram solving technique
- Start with the big numbers. A 15-clue in a 15-wide row fills completely; a 10-clue forces a guaranteed overlap in the middle.
- Use overlap logic everywhere: place a block at its leftmost and rightmost legal positions, cells common to both are certainly filled.
- Mark empty cells with an X as confidently as you fill squares, exclusions drive the second half of every solve.
- Revisit finished lines' crossings immediately; every new certainty cascades into the perpendicular clues.
- Never guess. If you are stuck, a forced cell exists somewhere you have not cross-checked, that is the puzzle's promise.
FAQ
How do I read a clue like '3 1 2'?
That row contains, left to right, a run of three filled cells, then a run of one, then a run of two, with at least one empty cell between runs. The gaps can be any size of one or more, and figuring out how much slack exists is the puzzle.
What is the overlap technique?
Slide a clue's block to its extreme left position, then its extreme right. Any cell filled in both scenarios must be filled in reality. It is the single most powerful nonogram move and often cracks a fresh grid wide open from the largest clues.
Do nonograms ever require guessing?
Properly constructed ones never do, every cell is decidable by logic, and this game's puzzles are built that way. If you feel forced to guess, some row-column cross-reference is still unexploited. The feeling of finding it is the whole hobby.
Why do my Xs matter if only filled cells make the picture?
Because exclusions are deductions. An X pins down where blocks cannot sit, which shortens the legal range of every clue in that line and creates new overlaps. Expert solvers place Xs more eagerly than fills.
