The puzzles on this page are played with JavaScript, which is not active in your browser, or whose file could not be loaded. Everything else on the site — the texts, the legal notice, the navigation — works without it.
Large Print Nonograms
Square by square, the picture appears
The numbers along the edge of the grid tell you how many squares to fill in, and in what order. You reason, you fill in, you cross out what stays empty — and a picture emerges from the grid.
Three puzzles to play
How to play
With the keyboard: the arrow keys move, Space fills in, X crosses out the square (and clears it if it already was), Backspace clears. With the mouse, each click goes from empty to filled, then to crossed out.
Why these puzzles can be solved without guessing
Most image-to-nonogram converters produce ambiguous grids: two different drawings fit the same clues, and you have to try your luck. This is the hard core of the problem, and it is known in the scientific literature.
We publish a puzzle only if it passes two checks: a single solution exists, and it can be reached by line-by-line deduction, without ever trying at random. The three puzzles above passed both checks before being placed on this page.
- Single solution — an exhaustive enumeration of the compatible arrangements; we stop as soon as a second solution appears.
- Pure logic — we solve using only what a single row or column forces on its own, until nothing moves any more. If the grid is not finished, it is rejected.
The printed book
- In the book: grids from 15 × 15 to 18 × 18, squares measured between 8.4 and 11.5 mm across the hundred printed puzzles. The three puzzles on this page fall within the same range: they too go from 15 × 15 to 18 × 18.
- Measured 18 pt type, in Luciole, on cream paper.
- Solutions checked one by one: no puzzle requires guessing.
- Four bonus puzzles, and a hidden word to find.
This book is not on sale yet. When it is, the link to order it will be here.