Do your nonogram clues
actually solve?

Paste the row clues and the column clues of any nonogram — also called picross, hanjie, griddler or paint by numbers — and this tells you which of four things you have: a puzzle with one clean answer (drawn for you), impossible clues plus the line that proves it, row and column totals that disagree, or a puzzle that is consistent but needs a guess because line logic runs out. A solver that only ever spins or prints a grid leaves you guessing which one it was. No sign-up, no upload: nothing you type leaves this page.

Numbers separated by spaces, e.g. 3 1 2. An empty row is 0 or a blank line. The grid size is taken from how many lines you type.

Load an example from our free pack:

Why won't my nonogram solve? The four answers

Most of the time a nonogram that "won't solve" is a nonogram that was copied down wrong. This page names which case you are in instead of failing silently:

The same solver that signs off the puzzles we publish

This is not a solver written for a web page. It is the routine that proves every puzzle we sell: a nonogram only ships after this code closes it from its clues alone and lands on exactly the picture it was drawn from. The build that produced this page re-ran that proof on all 110 of them — 100 in the book and 10 in the free pack — and refuses to publish if the copy running in your browser disagrees on a single cell.

The deduction it uses is the same four-rule set explained, with drawn examples, in how to solve nonograms step by step. If you want to get faster rather than get the answer, start there.

Where to get puzzles worth solving

10 free printable nonograms, with the answer key

A4 PDF, no sign-up. Every one of them closes with the logic above — that is what this solver checked before the file went out. Download the free pack — or play the same ten in your browser, no printer needed.

Pixel Logic — 100 nonograms with a picture reveal

The paid book: 100 puzzles in three sizes, each one proved to have a single solution reachable without guessing. See it on itch.io

Play five of them in your browser, free

The sampler runs in the page: fill, mark, and the picture appears when the grid closes. No download, no account. Play the free nonogram sampler on itch.io

Making your own instead of solving one?

Draw the picture and the nonogram checker counts the clues off it and answers the question this page can't: does your puzzle close on logic alone, or does it force a guess? It marks the cells that can't be decided.

Running a class or a group?

Nonograms as a logic lesson, with a lesson plan and printable sheets: nonograms in the classroom.