How to play nonograms

Nonograms (also known as picross, griddlers, or pic-a-pix) are logic puzzles that turn into pixel-art paintings when solved. No guessing — every square is a deduction.

The rules in one paragraph

You're given a grid and a list of numbers beside each row and each column. Those numbers tell you how many cells are filled in that line, in order, with at least one blank gap between each group. A clue of 3 2 on a 10-cell row means: three filled cells, then at least one blank, then two more filled cells. Your job is to figure out exactly which cells are filled using only logic — never guesswork. When every row and column matches its clues, a hidden pixel-art image appears.

5 steps to your first solve

1. Read the clues. Each number outside a row or column is a "run" of filled cells. Multiple numbers mean multiple runs, always in that order, always separated by at least one empty cell.
2. Fill the cells you're certain about. Start with the longest clues. On a 10-wide row with a clue of 8, the middle 6 cells are always filled no matter where the run begins. (This is called the overlap technique.)
3. Mark blanks with X. Cells you've proven can't be filled are just as important. Marking them with an X keeps you from making wrong moves later.
4. Alternate rows and columns. Every cell belongs to both a row and a column. Fill one cell from a row deduction, then re-check its column — that's usually where the next clue unlocks.
5. Reveal the image. Keep going. When the last run locks in, the grid reveals a hidden pixel-art painting — the reward for your logic.

A few tips that will save you minutes

Edge fill. A clue of k at the start of a row guarantees cells 1..k minus the offset are filled — when the full row is exactly the sum of clues + gaps, the whole line is forced.

Zero clues. A clue of 0 means the entire row or column is empty. Mark every cell with an X immediately.

Use X-marks aggressively. Every blank you confirm reduces the solution space for every other line passing through it.

If you're stuck, step away. The puzzle is solvable; you just haven't seen the deduction yet. Looking at a different row often unstuck the first one.

Glossary

Nonogram / picross / griddler / pic-a-pix

Different names for the same puzzle form — a logic puzzle where row and column clues determine which cells are filled.

Run

A consecutive group of filled cells in a single line. Each number in a clue describes one run.

Clue

The numbers outside the grid that describe a row's or column's run pattern.

Overlap technique

When a single clue is long relative to the line, some cells in the middle are guaranteed filled regardless of where the run starts — the overlap between leftmost and rightmost possible positions.

Mega / duo mode

A variant where row clues apply to pairs of rows as a union, so you deduce which cells go in which row using column clues. PixDojo's Duo Dojo uses this.