Nonograms

Turn an image into Nonogram clues

Nonogram clues are runs of filled cells. This tool builds those runs from your picture. It doesn't promise a puzzle you can solve by logic alone.

A normal Nonogram gives you numbers beside each row and column. A 4 means four filled cells in a row. A 2 1 means two filled, at least one empty, then one filled. Stack enough of those constraints and a well-made puzzle has one picture at the end. Photo conversions skip the "well-made" part. They color some cells, call the rest empty, and write down whatever runs that grid happens to contain. You can still solve it by looking at the preview. You might not solve it from the numbers only, because two different fillings can share the same runs, or the runs can be so specific that you're transcribing, not deducing.

Settings that produce a readable clue list

Use the image to Nonogram page. It starts at 15×15, square, 2 colors, dithering off, contrast up a bit. Two colors matter. The empty color menu defaults to the most common color, which is often the background. Filled cells are everything else. If the background is busy, the "empty" choice is wrong and the clues turn into static. Crop to a silhouette, raise contrast, and look at the preview before you copy numbers.

10×10 is kinder. 15×15 is a real puzzle size if the shape is simple: a heart, a mug, a cat's head. 25×25 from a face is usually a stack of 1s and 2s. Those clues are correct and miserable. Dithering makes this worse, because speckles are runs of length 1. Leave it off.

The output is plain text. Rows, then columns, one line each. Copy clues puts that text on the clipboard. A line that's just 0 is an empty row. Keep it. Solvers and human players both need to know the row is blank.

What to do with the clues

Print them, or type them into a sheet. Pixelate Tools doesn't ship a Nonogram player — for playable puzzles open NonogramGo. This page ships clue text and printable sheets for a picture you already have.

If the picture is the point and the puzzle isn't, you don't need clues. Stay on the pixel converter and export PNG. Clues throw away color. A 2-color nonogram of a sunset is a silhouette of a sun, which is fine, and it's not the sunset. The pixel art definition is the colored grid. The Nonogram is that grid collapsed to filled or empty.

A small honest example

A 5×5 letter T: top row is five filled cells, each row below has one filled cell in the center column, rest empty. Row clues read 5, then 1, 1, 1, 1. Column clues read 1, 1, 5, 1, 1. That puzzle is unique and obvious. A photo at 15×15 uses the same mechanic with worse manners. If copied clues look like a wall of single-digit numbers, the image was too detailed for the grid. Lower width, or raise contrast, until rows show a few solid runs. Then the text is worth saving.

Store the clue text next to a small PNG of the same grid. The PNG is the answer key. The text is the puzzle, such as it's. If you later change contrast and forget, the text and the picture drift apart and you'll solve a different image than the one you printed. Export both in one sitting.

When not to publish photo clues

Skip clue export when you need a fair logic-only puzzle, when the subject is a noisy forest, or when color carries the joke. Clues from photos are transcription aids, not curated Nonogram books. For playable daily puzzles, use NonogramGo instead.

Clue export checklist

Width 10–15 for a first try. Two colors. Dither off. Empty color matches real background. Preview silhouette readable. Copy clues once, paste to a text file named with width and date. Small PNG saved as answer key. If clues and PNG disagree, trust the PNG and regenerate text, not the other way around.

Row and column clue lines should stay in order. If you edit the text by hand, keep zeros for blank rows. A missing line shifts every solver downstream.

Questions

Keep going

• Image to Nonogram tool
• Play Nonogram
• What the grid is
• Photo walkthrough

Updated 30 September 2026