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Nonogram maker

Paint a picture on the grid and PuzzleForge writes the number clues. A built-in checker tells you if it can be solved by logic alone.

Grid size

Tap or drag to paint. Keyboard: arrow keys to move, Space to toggle.

Paint some squares to make a puzzle.

Mystery Picture

10×10

The numbers give the lengths of the runs of filled squares in each row and column, in order, with at least one gap between runs. Shade the grid to reveal the picture.

3566677642
0
2 2
4 4
10
10
8
6
4
2
0

Solution

How to solve a nonogram

Start with the big numbers. In a 10-wide row with the clue 8, the run must cover squares 3 to 8 whichever way you slide it, so those six can be shaded straight away. This “overlap” trick, then crossing off squares that can’t be reached, is exactly the line-by-line logic the checker uses to test your puzzle.

Making pictures that solve well

  • Bold, chunky shapes beat thin outlines: long runs give solvers a foothold.
  • Avoid 2×2 checkerboard patches. They can be flipped without changing any clue, which creates two answers.
  • Use the checker; if it fails, adjust the area around rows full of 1s.

Questions people ask

What is a nonogram?

A nonogram (also called picross, griddler or paint-by-numbers) is a grid puzzle where the numbers beside each row and column tell you the lengths of the runs of filled squares in that line. Solving it reveals a picture.

How do I make my own nonogram?

Tap or drag on the grid to paint your picture, or upload an image and adjust the threshold. The clues are calculated as you draw, and the checker tells you whether the puzzle can be solved without guessing.

What does "solvable by logic" mean?

The checker solves your puzzle one row or column at a time, the way a person does. If it can finish without guessing, the puzzle is fair and has one answer. If not, add or remove a few squares until it passes.

What grid size is best?

10×10 is a good first puzzle. 15×15 allows recognisable pictures. 20×20 and larger are for experienced solvers and print best one per page.

Is my uploaded image sent anywhere?

No. The image is converted to squares inside your browser and never uploaded.

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