How to solve Nonograms
A Nonogram is a grid with numbers along the top and left side. Shade the right cells and a pattern appears. You never need to guess: every puzzle on MiniGames Park can be finished with the five techniques below.
The rules
Each row and each column has a clue, a list of numbers. Every number is a block of consecutive filled cells. The blocks appear in the same order as the numbers, and there is at least one empty cell between two blocks.
So a row clue of 2 3 means: somewhere in the row there is a block of two filled cells, then one or more empty cells, then a block of three. Everything else in that row is empty. A clue of 0 means the whole line is empty.
One valid way to place clue 2 3 in a row of 8. The puzzle's columns decide which placement is the right one.
The puzzle is solved when every row and every column matches its clue. On MiniGames Park you fill cells you know are part of a block and cross cells you know are empty. Crosses are only notes, but experienced solvers use them constantly.
Technique 1: The overlap
This is the move that starts almost every puzzle. Take a big block and imagine pushing it as far left as it goes, then as far right. Any cells covered in both positions must be filled.
Clue 7 in a row of 10. Pushed left it covers cells 1 to 7; pushed right it covers 4 to 10. Cells 4 to 7 are certain.
A quick way to count it: the number of certain cells is the block length minus the free space. Here the free space is 10 minus 7, which is 3, so 7 minus 3 gives 4 certain cells. If a block is not bigger than the free space, the overlap gives you nothing yet.
The same idea works with several blocks. Add the blocks plus one gap between each pair, subtract from the line length, and that is your free space. Any block longer than the free space gets an overlap.
Technique 2: Lines that are full or nearly full
Sometimes the clue fills the line completely. Clue 4 1 3 in a row of 10 needs 4 + 1 + 1 + 1 + 3 = 10 cells, with the two gaps counted. There is only one way to place it.
Zero free space: the whole row is decided in one go.
Look for these first. A clue equal to the line length fills the line, and a clue of 0 crosses it out. Lines with only one or two spare cells are nearly as good, because every block in them gets a large overlap.
Technique 3: Using the edges
Once a few cells are filled, the walls of the grid start to help. If a filled cell sits close to an edge, the block that covers it cannot slide past the wall.
Clue 3, and cell 2 is already filled. The block must start at cell 1 or 2, so cell 3 is filled too, and cells 5 to 8 are out of reach.
The rule of thumb: a block that has to include a known cell can only start a limited distance before it. Work out the earliest and latest start, and apply the overlap to that smaller window. Anything the block can no longer reach gets a cross.
Technique 4: Close completed lines
When every block in a line is in place, all the remaining cells in that line are empty. On MiniGames Park the clue turns green when a line matches, which is your signal to cross out the rest.
This sounds obvious, but it is where most progress comes from in the middle of a puzzle. Each cross you add is information for the line running the other way.
Technique 5: Let crosses split the line
Crossed cells cut a line into separate pieces. A piece too short for any remaining block must be empty. For example, if a row's only clue is 4 and a gap of three cells sits between two crosses, that gap cannot hold the block, so cross it too.
The same thinking works in reverse. If a filled block is already as long as the biggest number in the clue, it is complete, so the cells on both ends are empty. And if two filled runs are separated by a single unknown cell, check what filling it would create: if the joined block would be longer than every number in the clue, that cell must be empty.
A solving routine that works
- Scan for full lines, empty lines and lines with very little free space.
- Apply the overlap to every line with a big block.
- Switch direction. Every new fill or cross in a row is a fact about a column.
- Use the edges and any known cells to narrow where each block can go.
- Cross out completed lines and pieces too small to hold a block.
- Repeat the passes until the picture is finished.
You can practise each step on a 5×5 puzzle. Small grids are almost entirely overlaps and full lines, so they build the habit fast. When those feel easy, move up to the daily 10×10.
Where Nonograms come from
Nonograms were devised in Japan in the late 1980s. Graphic designer Non Ishida and puzzle author Tetsuya Nishio came up with the idea independently around the same time, and the English name comes from Ishida's first name. British newspaper readers met them in The Sunday Telegraph in the early 1990s, and handheld games later made them famous as Picross.
Today they go by many names, including Griddlers, Hanjie, Paint by Numbers and Pic-a-Pix. The rules are the same everywhere, so anything you learn here works in any Nonogram book or app.
Common questions
Do I ever need to guess?
Not on MiniGames Park. Our generator only publishes grids that a line-by-line solver can finish without guessing, which also means each grid has exactly one solution. Some printed puzzles do require trial and error, but ours never will.
Why do my puzzles look like abstract patterns?
Our grids are generated to be good logic puzzles first, so many look like patterns or symmetrical shapes rather than a drawing of a cat. The solving experience is the same, and you get a fresh puzzle every time.
What is the fastest way to get better?
Play daily and always cross out empty cells. Most beginners only fill, and they miss half the information the grid is giving them.