Fill in cells using the number clues for each row and column. Five sizes from 5×5 to 15×15, and every puzzle has one solution you can reach without guessing.
What is a Nonogram?
A Nonogram is a logic puzzle in which you work out which cells of a grid are filled, using the numbers beside each row and above each column, which give the lengths of the filled blocks in that line. You solve it by reasoning about each line in turn, row by row and column by column, until the whole grid is decided.
Nonograms are often used to draw a hidden picture. Ours are random patterns made fresh for each game, so the result is an abstract design, and every puzzle is checked so it has exactly one solution that you can reach by logic, without guessing.
How to play Nonogram
Reading the clues: each row has a list of numbers on its left, and each column has a list above it. The numbers are the lengths of the runs of filled cells in that line, in order. A row clue of 3 1 2 means a run of 3 filled cells, then a run of 1, then a run of 2, reading left to right, with at least one empty cell between runs. There may be any number of empty cells before the first run, between runs and after the last one.
Marking cells: choose Fill or Cross with the buttons under the grid. Tap a cell to fill it or mark it with a cross, or drag along a row or column to mark several cells at once. A cross means you know the cell is empty. Tapping a cell that already has the current mark clears it again. Crosses are only notes for yourself; they are not needed to finish.
Checking progress: when a row or column matches its clue, its numbers turn grey. The game does not point out mistakes. As on paper, you find out when the puzzle is solved: the grid is complete when the filled cells match every clue.
Sizes: there are five grid sizes, 5 by 5, 8 by 8, 10 by 10, 12 by 12 and 15 by 15. Every row and every column has at least one filled cell, so a clue of 0 never appears.
Nonogram solving techniques
Overlap. If a run is longer than half its line, the middle part has to be filled however the run is placed. Slide it as far left as it can go, then as far right; the cells covered both times are filled. In a line of 10, a clue of 8 always fills the middle 6 cells, and a clue of 6 fills the middle 2.
Overlap with several runs. Add up the runs plus one gap between each pair. Subtract that from the line length to get the slack. Any run longer than the slack has cells you can fill now: as many as its length minus the slack. In a line of 10 with clue 3 4, the minimum is 3 + 1 + 4 = 8, so the slack is 2, the 4 gives 2 sure cells and the 3 gives 1.
Full lines. When the runs plus the gaps add up to exactly the line length, the slack is zero and the whole line is known at once. On a 5 by 5 grid, the clues 5, 3 1, 1 3, 2 2 and 1 1 1 each fill a whole line by themselves.
Edges and anchors. A filled cell close to the edge must belong to the first run, so the run has to reach it. If the first run is 4 and the third cell from the left is filled, cells 3 and 4 are certain. When a run is complete, put a cross on each side of it.
Crossing out. Cells that no run can reach are empty. Once all runs of a line are placed, cross every remaining cell. Crosses matter because they become information for the lines that cross them.
Go back and forth. Every new fill or cross in a row gives the columns that pass through it something new to work with. Because each puzzle here can be solved line by line, if you feel you need to guess, there is a deduction you have missed. Go back over the lines with the least slack.
Grid sizes and other nonogram variants
Our Nonogram offers five sizes from 5 by 5 to 15 by 15. A 5 by 5 grid takes a minute or two and is good for learning the techniques above. At 15 by 15, the overlap trick still gives a start, but most of the grid comes from combining rows and columns many times.
Our puzzles fill a little over half of the grid, which gives large clues and lots of overlap to start from. Other variants exist, such as puzzles in several colours, where runs of different colours need no gap between them, and puzzles designed by hand to show a picture.
Where Nonograms come from
Nonograms were invented in Japan in the late 1980s. Non Ishida, a graphic designer, and Tetsuya Nishio both came up with puzzles of this kind around 1987. The name Nonogram joins Ishida's first name with the word diagram.
The puzzles spread to newspapers, puzzle magazines and computer games around the world, under several names, including Griddlers, Hanjie and Paint by Numbers.
Play Nonogram on Hevagames
Our Nonogram runs in the browser on phones, tablets and computers, with nothing to download. Tap or drag to mark cells; a drag stays in the row or column where it started. With a mouse, a right click puts a cross. On a keyboard, the arrow keys move the cursor, F fills, X crosses, M switches between Fill and Cross, and U or Ctrl+Z undoes. The row and column of the cursor are highlighted.
Undo steps back through your marks. The puzzle in progress and your chosen size are saved in your browser, so you can close the page and carry on later. The timer runs while you play, and your best time is kept for each size. A solved puzzle scores 10 points per cell of the grid minus the seconds you took, with at least 10 points.
How to play
- 1The numbers next to each row and above each column give the lengths of the filled runs in that line, in order.
- 2Runs in the same line are separated by at least one empty cell.
- 3Pick Fill or Cross at the bottom, then tap a cell or drag across a straight line of cells. Crosses mark cells you know are empty.
- 4The puzzle is solved when the filled cells match every clue.
Controls
Tips
- Start with large clues. In a 10-cell line, a clue of 8 always covers the middle 6 cells.
- A clue of 0 never appears; every row and column has at least one filled cell.
- Clue numbers turn grey once their line matches them.