Nonogram Puzzle Generator
Draw a picture or trace an image into a grid and get a printable nonogram, with a solver that tells you honestly whether the clues can be worked out by logic alone.
Verified: a line-by-line solver rebuilt this exact picture from the clues alone, so the puzzle has a single solution and never needs a guess.
Click a cell to toggle it
Filled cells are shown in brand blue while you edit. Press “Show the picture” to preview the finished artwork in black.
Trace a picture from an image
Solution as text
..###..... .##..#.#.# ..#..#.... #####.#.#. .#.##.###. #...####.. ..#..#.### #..#.#.#.# ####.###.# #...#.##.#
The clues are read straight off your picture: each row and column is walked once and its runs of consecutive filled cells become that line’s numbers. A line solver then works the other way, enumerating every arrangement each clue allows and keeping the cells that agree in all of them — so the badge above tells you honestly whether the puzzle can be solved by deduction alone. Nothing is uploaded; the image you trace is sampled inside your browser and never leaves your device.
What is the Nonogram Puzzle Generator?
A nonogram — also called Picross, Griddlers or Hanjie — hides a picture behind number clues. Each clue lists the runs of filled cells in that row or column, and solving means working out which arrangement fits.
- Grids from 5 by 5 to 20 by 20 with click-to-toggle editing
- Seeded random fill with an adjustable density slider
- Trace any image into the grid using a darkness threshold
- Line solver reports whether the puzzle needs a guess
- Puzzle and solution exported separately as PNG
- Clues and the picture both copyable as plain text
How to use the Nonogram Puzzle Generator
- 1
Set the number of columns and rows, from 5 up to 20.
- 2
Fill the grid from a seed, click individual cells to toggle them, or trace an uploaded image.
- 3
Check the badge under the stats — green means the clues can be solved by pure logic.
- 4
Press Show the picture to preview the finished artwork in black.
- 5
Download the puzzle PNG for printing, and the solution PNG as your answer key.
About the Nonogram Puzzle Generator
A nonogram — also called Picross, Griddlers or Hanjie — hides a picture behind number clues. Each clue lists the runs of filled cells in that row or column, and solving means working out which arrangement fits. This tool works backwards: draw the picture you want, and the clues are read straight off it.
You can click cells one at a time, fill the grid from a seed with a density slider, or drop in an image and have it traced by darkness threshold. Because the fill is seeded rather than truly random, the same seed and size always rebuild the same picture, so a puzzle you liked can be recreated exactly.
A line solver then works the other way round, enumerating every arrangement each clue allows and keeping only the cells that agree in all of them. The badge above the grid tells you honestly whether your puzzle can be deduced without guessing. Everything runs in your browser and any image you trace stays on your device.
Frequently asked questions
How do nonogram clues work?
Each number is the length of one unbroken run of filled cells in that line, listed in order, with at least one blank between runs. A row clued 3 1 has a block of three, then at least one empty cell, then a single filled cell.
Does every nonogram have exactly one solution?
No. A randomly drawn picture often produces clues that several different pictures would satisfy. This tool runs a line solver on your grid and tells you whether the clues pin the picture down completely or would leave a solver guessing.
What makes a good nonogram puzzle?
Large connected shapes with clear edges, and a fill density somewhere near half. Very sparse or very dense grids produce clue lists that are either trivial or ambiguous. Simple silhouettes traced from an image usually work best.
Can I make a nonogram from a photo?
You can trace one, but photographs rarely work well. The image is scaled down to your grid and each cell becomes filled or empty based on a darkness threshold, so a high-contrast silhouette or logo gives a far more readable puzzle than a photo.
What size nonogram should I start with?
A 10 by 10 grid takes a few minutes and is a comfortable introduction. 5 by 5 is almost trivial, while 20 by 20 is a serious sitting. Larger grids also make it much more likely the clues will need a guess somewhere.
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