Nonogram

How to play Nonogram

A nonogram is a grid of blank cells with numbers along the top and the left side. Your job is to decide which cells are filled and which are empty. When every cell is right, the filled cells form a small picture.

The numbers beside a row (or above a column) describe the runs of filled cells in that line, in order. A clue of 3 1 means a run of three filled cells, then at least one empty cell, then a single filled cell. A clue of 0 means the whole line is empty. Tap a cell to fill it, drag along a row or column to fill several at once, and use the Cross tool (or right-click) to mark cells you are sure are empty. A clue fades once its line matches.

Solving techniques

• Start with the big numbers. In a 10-cell row, a clue of 8 must cover the middle six cells whichever way you slide it. Fill the overlap: those cells are certain.
• Add the clues up. For a clue like 4 3 in a 10-cell row, the runs plus the one gap between them take 4 + 1 + 3 = 8 cells. With only two spare cells, the left run must cover cells 3 and 4, and the right run cells 8 and 9.
• Cross off what can't be filled. Once a line's runs are all placed, every other cell in it is empty. Crossing them out is what unlocks the lines that cross them.
• Work the edges. A filled cell touching the border must be the start of the first (or last) run, so you can extend it by that run's full length and cross the cell after it.
• Swap between rows and columns. Every cell belongs to one row and one column. Each new fill or cross in a row is a fresh clue for the column it sits in, and the puzzle usually falls by bouncing between the two.

Is every puzzle fair?

Yes. Each picture here is randomly generated and then handed to a solver that is only allowed to reason one line at a time, the way a person does. A puzzle is used only if that solver can finish it, so every nonogram has exactly one solution and can always be solved without guessing. The 5×5 grids are a quick warm-up; the 10×10 grids are a proper coffee-break puzzle.

The history of the nonogram

Nonograms began in Japan in 1987. The graphic designer Non Ishida won a Tokyo competition by making pictures out of lit and unlit skyscraper windows, and from that idea she began drawing pictures on grids with number clues. In the same year the Japanese puzzle maker Tetsuya Nishio arrived at the same kind of puzzle on his own. Ishida's "window art" puzzles were published in Japan in 1988.

The puzzles reached Britain in 1990, when the puzzle collector James Dalgety named them nonograms after Non Ishida, and The Sunday Telegraph began printing one every week. They have since collected a string of names: Griddlers, Hanjie, Paint by Numbers, Pic-a-Pix and, after Nintendo's handheld games of the mid-1990s, Picross. Whatever the name, the rules are the same as the ones above.

Frequently asked questions

Is a nonogram the same as Picross, Griddlers or Hanjie?

Yes. Picross, Griddlers, Hanjie, Paint by Numbers, Pic-a-Pix and Japanese crosswords are all names for the same puzzle: number clues on each row and column describe runs of filled cells, and the solution forms a picture.

What does a clue like 2 1 3 mean?

It means that line contains a run of two filled cells, then a single filled cell, then a run of three, in that order from left to right (or top to bottom), with at least one empty cell between each run. There can be extra empty cells at either end.

Do I have to mark the empty cells?

No. The puzzle is solved as soon as the filled cells match every clue, so crosses are optional. They are simply a helpful way to record cells you have already proven empty.

Does every nonogram have one solution?

Every puzzle on this page does. Each one is checked by a line-by-line solver before you see it, which guarantees a single solution reachable by logic alone, with no guessing needed.

Is it free, and is my best time saved?

It is completely free with no sign-up. Your best time is saved in your own browser, on your device, and nothing is uploaded.