Home / Catalog / Nonograms / Rules
How to play · Rules

How to Play Nonograms

The complete guide: how to read the number clues for rows and columns, fill in cells and mark empty ones with a cross, modes, checking your solution and controls on muta.pro.

Play now

In brief

Goal
Reveal the hidden picture
Players
1
Game
10–30 min
Difficulty
Medium
Genre
Puzzle

Goal of the game

A nonogram is a logic picture puzzle for one player. Using the numbers set beside the rows and columns, you need to fill in the correct cells so that a pixel image appears on the grid. The solution is unique and derived strictly by logic — no guessing. The game is won when the arrangement of filled cells exactly matches the reference.

Setup

Choose a field size — 5×5, 10×10 or 15×15 — and a level from the list on the right. In front of you is an empty grid: to the left of each row and above each column are the number clues. Solved levels are marked with a checkmark ✓, and your best time is stored next to it. The timer starts on your first action and stops when the picture is assembled.

How to read the clues

Numbers are blocks

Each number beside a row or column is the length of a solid block of filled cells. "5" means five filled cells in a row within that line.

Several numbers

If there are several numbers, the blocks go in the same order and are separated by at least one empty cell. "3 2" means three first, then a gap, then two.

Fill in the correct cells

Left click fills a cell (clicking again removes the fill). This is how you mark the cells that definitely belong to the picture.

Mark the empty ones

Right click places a cross ✕ on a cell that is certainly empty. It is only a hint for you and does not affect the check — but it greatly helps you avoid confusion.

Cross-reference the lines

Solve starting from the most "dense" rows and columns: where blocks nearly fill a line, some cells are determined unambiguously. A completed clue gets crossed out.

Check back and forth

After filling cells by rows, check the columns, and vice versa. Step by step the grid converges to its single solution.

Checking and winning

The picture is considered assembled when every cell matches the reference: all the needed ones are filled and there are no extras. The "✓ Check" button highlights wrong fills in red and briefly shows how many cells are incorrect, after which it clears them. The results window shows the time, the number of mistakes and hints used; for a record time a "🏆 New personal record!" mark appears. The "Next →" button moves on to a new level of the same size.

Controls on muta.pro

🖱️
Fill / cross
Left click fills a cell, right click places an "empty" cross. You can switch the mode with the "⬛ Fill" and "✕ Empty" buttons.
Check
"✓ Check" looks for wrong fills and highlights them in red.
💡
Hint
"💡 Hint" reveals one correct cell. It is counted in the final statistics.
Reset and size
"🧽 Clear" erases the field, "↻ New / reset level" starts over, and the 5×5/10×10/15×15 buttons change the size.

Tips for beginners

Start with big numbers

Blocks that almost fill a line give guaranteed cells in the middle — start with those.

Crosses save time

Mark the cells that are certainly empty: this way you won't fill anything extra and you'll see the block boundaries faster.

Alternate the axes

Solved a few rows — immediately check the columns. New information opens up the next moves.

Don't guess

In a nonogram everything is derived by logic. If you hit a dead end, look for a line with an unambiguous solution instead of placing cells at random.

The overlap method

The main nonogram technique is overlap. Mentally shift a block to its far-left and far-right positions within the line: the cells filled in both cases belong to the picture in any arrangement. You can fill them in risk-free, even without knowing the block's exact position.

4
4
4

A "4" block in a line of 5 cells: on the left and on the right it overlaps on the middle cells — those we fill in for sure.

Count with the formula

The guaranteed cells are exactly "block length minus free space". A 4 block in a line of 5 gives 4−1=3 overlap, a 7 block in a line of 10 gives 7−3=4.

Account for several blocks

With a "3 2" clue, count the minimum length: 3+1+2=6. The remaining slack is the freedom the blocks have to shift.

Start with long lines

The larger the sum of the numbers relative to the line length, the wider the overlap. Such rows and columns give the first correct cells without a single guess.

Logic of edges and boundaries

When a filled cell appears in a line, work from it. A cross at the edge or an already known block often pins the next block against the wall, and it is revealed unambiguously. The edges of the grid are the most fruitful place: there a block has nowhere to shift.

3

Clue "3" and the first cell is occupied: the block is pinned to the left edge, the rest of the line we close off with crosses.

Build out from the fill

Have a filled cell and a "4" clue? Count off four in a row in the possible direction — part of it is completed unambiguously.

Close off the block with crosses

As soon as the block length is reached, place crosses on both sides. This fixes the boundaries and opens up the neighboring lines.

Look for narrow gaps

A gap between crosses shorter than the nearest block — fill it with crosses: the block won't fit there.

Proof by contradiction

When direct logic stalls, testing a hypothesis helps. Mentally fill in a disputed cell and follow the chain along its row and column. If a clue is violated somewhere — the cell must be empty; place a cross. This way the contradiction itself points to the right move.

2
?

If you fill in "?", the line will have a block of three cells instead of "2" — so there is a cross here.

Test a single cell

Take not the whole line, but one specific doubtful cell. A short chain of consequences leads faster to a contradiction or confirmation.

Count the remaining tail

Add up the not-yet-placed blocks with their required gaps. If the sum doesn't fit into the rest of the line — your hypothesis is wrong.

Don't turn it into brute force

On a correct nonogram everything is derived by logic. If you have to guess several cells in a row at random — you missed a simpler move in another line.

Common mistakes

Most failures come not from difficulty but from inattention to block boundaries and the order of the numbers. Let's break down the typical traps that cause the picture to "not come together" and the "Check" to highlight extra cells.

  1. Mixing up the order of blocks. Numbers are read strictly left to right and top to bottom. "3 1" means a three first, then a one, not the other way around.
  2. Forgetting the required gap. Between adjacent blocks there is always at least one empty cell. "2 2" in a line of 4 cells is impossible — you need at least five.
  3. Not placing crosses. Without marking the empties it's easy to fill something extra and lose the boundaries. A cross is a proven fact, not a decoration.
  4. Solving only one axis. After filling the rows, they forget to cross-check the columns. It is precisely at the junction of the axes that new unambiguous cells are born.
  5. Guessing at a dead end. A cell filled at random wrecks the whole chain. Better to go back to a dense line and find an honest conclusion.

Frequently asked questions

What do the numbers on the side and top mean?
They are the lengths of solid blocks of filled cells in that row or column, in the given order.
Do I need to place crosses?
No, they do not affect winning. But they are a great help for marking empty cells and avoiding mistakes.
What field sizes are available?
Three: 5×5, 10×10 and 15×15. Levels within each size are drawn from a ready-made set of pictures.
Can I check myself?
Yes, the "✓ Check" button highlights the incorrect cells and shows how many there are.
What is the overlap method?
It is a technique where you mentally shift a block to its far-left and far-right positions, and the cells filled in both cases turn out to be correct in any arrangement. You can fill them in without knowing the block's exact position.
How do I count the guaranteed cells in a line?
Subtract the free space in the line from the block length. For example, a "4" block in a line of five cells gives 4−1=3 overlapping cells, and a "7" block in a line of ten gives 7−3=4 correct cells.
Why is there always an empty cell between blocks?
Otherwise two blocks would merge into one and the clue would be a different number. That is why the minimum length for "3 2" is 3+1+2=6 cells.
What should I do if the solution reaches a dead end?
Test the disputed cell by contradiction: mentally fill it in and follow the chain. If some clue is violated, the cell is empty. Usually it is easier to find another dense line with an unambiguous conclusion.
Do I have to start with the largest numbers?
Not necessarily, but it pays off: the larger the sum of the numbers relative to the line length, the wider the overlap zone and the more cells open up at once without guessing.
Can a nonogram be solved without a single guess?
Yes. A correct nonogram on muta.pro has a single solution derivable by pure logic. If you had to guess, it means you missed a simpler move in a neighboring row or column.
Ready for a game?
Create a room, invite a friend by code or play against a bot.

Similar games