Nonogram
How it works
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1
Choose a grid from the list.
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2
Click a cell to fill it, click again to cross it out (deduced empty), and a third time to clear it.
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3
"Check" tells you if your grid is correct so far; "Hint"/"Solve" help if you get stuck.
Each row and column shows the length of its blocks of filled cells, in order: it's up to you to work out which cells to fill to reveal the hidden picture.
Click: fill a cell. Right-click (or click again): cross it out (deduced empty).
What is a nonogram?
A nonogram (also called picross or griddler) is a logic puzzle where every row and column carries a sequence of numbers indicating the length of its blocks of cells to fill, in order, separated by at least one empty cell. By cross- referencing these clues, you can work out, cell by cell, which ones to fill - until a picture appears. Unlike Sudoku, this isn't centuries old: it was invented independently in the late 1980s by two game designers, one Japanese and one British, before spreading under different names in different countries.
How to approach it
- Start with the most constrained clues: a row with a single large block close to the grid's full width often has cells you can fill in right away.
- Whenever a cell is filled or crossed out, always reconsider the rows and columns crossing it: new information can unlock a deduction elsewhere.
- Cross out (don't just leave blank) cells you're sure will never be filled: it keeps track of what's already been deduced versus what's still uncertain.
Frequently asked questions
How do I read the clues shown above and to the left of the grid?
Each number is a block of consecutive cells to fill on that row or column, in the order they're written, separated by at least one empty cell. For example, the clue "3 1" means a block of 3 filled cells, then at least one empty cell, then a single filled cell.
Why isn't there a random grid generator?
Generating a grid that is both logically solvable (without having to guess between several possibilities) and that actually looks like something recognizable is notably harder to automate than for Sudoku. The grids offered here were each designed and verified individually rather than generated.