How to Play Nonogram Puzzles
Everything you need to know to solve nonograms confidently, from basic rules to advanced strategies.
The Rules
A nonogram consists of a rectangular grid of cells. Each cell must be either filled or empty. Along the top and left side of the grid are numeric clues that tell you which cells to fill in.
Understanding Clues
- Each number represents a consecutive group of filled cells in that row or column.
- Multiple numbers mean multiple groups, separated by at least one empty cell.
- The groups appear in the order listed, from left to right (rows) or top to bottom (columns).
- A clue of "0" means the entire row or column is empty.
For example, a row clue of 3 1 in a 7-cell row means: 3 consecutive filled cells, then at least 1 empty cell, then 1 filled cell.
Step-by-Step Guide
Look for Full or Near-Full Rows
Start by finding rows or columns where the clues fill most of the line. If a row has 10 cells and the clue is "10", fill the entire row. If the clue is "8", you know the middle 6 cells must be filled (the overlap between pushing the block all the way left and all the way right).
Use the Overlap Technique
For any line, imagine sliding the clue blocks as far left as possible, then as far right as possible. Cells that are filled in BOTH positions must be filled. This is the most fundamental solving technique.
Mark Confirmed Empty Cells
When you know a cell cannot be filled, mark it with an X. If a clue is "0", mark the entire line. If a filled group is complete (bounded by edges or known empty cells), mark the cells on either side as empty.
Complete Bounded Groups
If a filled group touches an edge or known empty cell and must extend in one direction, fill in the remaining cells. For example, if the first clue is "3" and the first two cells are filled but the third is unknown, fill the third.
Iterate Between Rows and Columns
Every cell you determine helps constrain the intersecting row or column. Alternate between analyzing rows and columns. With each pass, you'll uncover more cells.
Tips & Strategies
Start Simple
Always process the easiest lines first — full rows, zero rows, and lines with large clues relative to the grid size.
Never Guess
Every cell should be determined by logic. If you're unsure, look for a different line to work on.
Use Edge Logic
Cells at the edges are often easiest to determine. If the first clue is large, the first few cells are likely filled.
Count the Minimum
Add up all the numbers in a clue plus the minimum gaps between them. Compare this to the line length to find overlaps.
Cross-Reference
After determining cells in a row, immediately check the affected columns, and vice versa.
Mark Liberally
Mark empty cells (X) early and often. Known empty cells are just as valuable as filled ones for solving.
Frequently Asked Questions
What is a nonogram?
A nonogram is a picture logic puzzle where you fill cells on a grid according to numeric clues to reveal a hidden image. They are also known as Picross, Griddlers, or Hanjie.
Do you need to guess in nonograms?
No. A well-designed nonogram can always be solved through logic alone. Every puzzle on this site is uniquely solvable without guessing.
How long does it take to solve a nonogram?
A simple 5×5 puzzle can be solved in under a minute. Larger puzzles like 15×15 or 20×20 may take 15 minutes to over an hour depending on difficulty and your experience level.
What is the difference between nonograms and Picross?
They are the same type of puzzle. "Picross" is Nintendo's trademarked name for nonograms, used in their popular series of puzzle games for Game Boy, DS, and Switch.
Are nonograms good for your brain?
Yes! Solving nonograms exercises logical reasoning, pattern recognition, and spatial awareness. Regular puzzle solving is associated with improved concentration and cognitive function.
Ready to Play?
Put your new skills to the test with our free nonogram puzzles.