A nonogram (also called picross, griddlers or paint by numbers) is a grid of empty cells with a list of numbers beside each row and above each column. Those numbers are the lengths of the filled runs. Fill the grid correctly and a picture appears.
It is the most satisfying logic puzzle on PlayJoy because it never requires guessing: every board we publish is verified to have exactly one solution before it goes live.
Read the overlaps before you read the clues
For any line, add up the clue numbers and add one blank between each block. If that total equals the line length, the line is completely determined — fill it in immediately without thinking further.
If the total is close to the line length, the overlapping region between the leftmost and rightmost possible placement is guaranteed filled. Mark those cells first on every line before doing anything else; this single pass solves most 5×5 boards outright.
Work the edges, then chase the consequences
Edge rows and columns have fewer possibilities, so they usually resolve first. Every time you fill a cell, immediately re-read the perpendicular clue that passes through it — a single filled cell often forces its entire crossing line.
How PlayJoy guarantees a unique picture
Our generator paints a candidate pattern, derives the clues, and then runs a constraint-propagation solver over the result. If the solver cannot resolve the grid to a single answer, the pattern is thrown away and a new one is drawn. Only uniquely solvable boards are published.
How Nonogram is scored
score = (difficulty × 12) ÷ seconds ÷ (1 + 0.3 × mistakes)
What it trains
- Logical Reasoning
- Pattern Recognition
Frequently asked questions
Is a nonogram the same as picross?
Yes. Nonogram, picross, griddlers and paint-by-numbers all describe the same rule set — fill runs of cells described by the clue numbers.
Do I need to guess?
No. Every PlayJoy nonogram is verified to have exactly one solution reachable by pure deduction.
What sizes do the daily boards use?
Level one is 5×5, level two is 8×8, level three is 10×10.
Is there a penalty for wrong cells?
There is no mistake counter, but wrong cells will eventually contradict a clue and slow you down, which lowers your score.