How do you play nonograms?

Every row and column has a clue: the lengths of its runs of filled squares, in order. A row marked 2 1 holds a run of two filled squares, then at least one empty square, then a single filled square, so in a row of five the squares 1, 2 and 4 read 2 1. Fill squares until every row and column reads as its clue, and the picture appears. Here, a tap or click fills a square and a second one empties it, the Cross tool marks squares you know are empty, and dragging along a row or column marks several squares in one stroke.

Does every nonogram here have exactly one solution?

Yes. Each puzzle starts as a candidate picture drawn from its seed: random squares, usually smoothed into shapes and sometimes mirrored. Its clues go to a solver, which solves every row and column on its own, repeats until nothing changes, and where squares are still open, tries them both ways to see whether a second solution exists. The picture is offered only if exactly one solution turns up. A candidate with two solutions, or one the search cannot settle within its step limit, is dropped and the next candidate from the same seed is tried, up to 60. If none of the 60 passes, the page says so and names the next seed to try instead of showing a doubtful grid.

Will I ever have to guess?

No. Having one solution is not the only test: the solver must also reach it one row or column at a time, working only from each line's clue and the squares already settled. A grid that has one solution but can only be finished by trying a square both ways is dropped too. So every puzzle offered here can be finished by reasoning about single rows and columns, and a Hint always has a line to point at while your marks are correct.

What does the Hint button show?

It works in order. First it names any row or column whose marks cannot fit its clue at all, which also shows as a red clue. Next it names a row holding a mark that does not match the solution. Otherwise it picks the row or column where the clue and your marks settle the most unmarked squares, outlines those squares on the board and says in words which ones to fill and which to cross. It never places a mark for you. Each hint adds one to the hint count, which shows beside your progress, and a solved puzzle keeps its count in the list of recent puzzles.

Can I print a nonogram?

Yes. Print sends a sheet with the clue grid and empty squares, headed with the size and seed, plus a short note on the rules. Tick the box to add the answer on a second page. The squares print at 14 mm on a 5 x 5 board and shrink to 9 mm on a 15 x 15, so the larger grids still fit with their clues on one page. Copy puts the same clues and grid on the clipboard as text, with any marks you have made.

What is the seed, and can I play the same puzzle again?

The seed is a whole number from 1 to 999999 that decides the picture. The generator draws its random numbers from a fixed formula seeded by the size and the seed, so the same pair gives the same puzzle on any device. The size and seed of the puzzle on the board are shown above it and in the Seed box. To open a puzzle again, choose its size, type its seed and press Play seed. New puzzle picks a random seed at the chosen size.

Is my progress saved?

Yes, in this browser only. The puzzle on the board, your marks, its hint count, the tool you chose, and up to 11 earlier puzzles you had started are kept, so a reload or a later visit opens where you left off. Resume reopens an unfinished puzzle with its marks, and Play again reopens a solved one on an empty grid. Undo reaches back through up to 400 strokes made since the puzzle on the board was opened in this visit. Nothing is uploaded, and the Start over button at the top of the page forgets all of it. If the browser refuses storage, the page says so and the puzzle still plays.

Nonograms

Play picture logic puzzles made on this page, from 5 x 5 to 15 x 15. Each one is drawn from a seed and offered only after a solver has found exactly one solution and reached it one row or column at a time, so no puzzle here needs a guess. Fill squares, cross the ones you know are empty, drag along a line to mark several at once, and undo a stroke in one step. A clue greys out when its line matches it and turns red when the marks in that line cannot fit it. Hint names a line to work on next, or the line holding a wrong mark. Your progress and your recent puzzles stay in this browser, the same size and seed make the same puzzle on any device, and any puzzle prints as a clue grid, with its answer on a second page if you want it.

puzzleno puzzle yet

Setting up the board

Your saved puzzle, or a new one, appears here in a moment.

progresssaved once you play

filled: none yet
crossed: none yet
rows met: none yet
columns met: none yet
hints: none yet
solutions: none yet
keys: arrows, Space fill, X cross

Setting up the board.

Size

Seed

Filled

none yet

Clues met

none yet

Solutions

none yet

Print the answer on a second page

Tap or click a square to fill it and again to empty it, or switch the tool to Cross to mark a square you know is empty. Drag along a row or column to mark several at once: a stroke only changes squares like the one it started on, and Undo takes it back in one step. With a mouse, a right-click puts a cross on or takes it off. On a keyboard, the arrow keys move, Space puts a fill on or off, X does the same for a cross, Backspace clears, and Ctrl+Z or Cmd+Z undoes. A clue turns grey when its line reads exactly as the clue, and red when the marks in its line cannot fit the clue at all. Hint names a line to work on next, or the line holding a wrong mark. The size and seed on the board make the same puzzle again anywhere, and your progress stays in this browser.

Your recent puzzles

No earlier puzzles yet. Each puzzle you leave after marking it is kept here with its seed and your marks, up to 11, so you can go back to it.

How clues and the check work

Filled cells 1, 2, 4a five-cell row
clue 2 1
Filled cells 1 to 4a five-cell row, no gap
clue 4, not 2 2: separate runs need at least one empty cell
A grid with a second solutionfound by the solver
2 solutions found, so not offered, nor is one the search cannot settle within its step limit

Accuracy. Every puzzle is generated here from an original seeded pattern, never copied from a puzzle pack. A grid is offered only when the solver finds exactly one solution and reaches it one row or column at a time; one with two solutions, one that needs a guess, or one the search cannot settle within its step limit is dropped. The clues are the exact run lengths of the filled squares, and there is no difficulty rating, because none is measured.

Common questions

How do you play nonograms?: Every row and column has a clue: the lengths of its runs of filled squares, in order. A row marked 2 1 holds a run of two filled squares, then at least one empty square, then a single filled square, so in a row of five the squares 1, 2 and 4 read 2 1. Fill squares until every row and column reads as its clue, and the picture appears. Here, a tap or click fills a square and a second one empties it, the Cross tool marks squares you know are empty, and dragging along a row or column marks several squares in one stroke.
Does every nonogram here have exactly one solution?: Yes. Each puzzle starts as a candidate picture drawn from its seed: random squares, usually smoothed into shapes and sometimes mirrored. Its clues go to a solver, which solves every row and column on its own, repeats until nothing changes, and where squares are still open, tries them both ways to see whether a second solution exists. The picture is offered only if exactly one solution turns up. A candidate with two solutions, or one the search cannot settle within its step limit, is dropped and the next candidate from the same seed is tried, up to 60. If none of the 60 passes, the page says so and names the next seed to try instead of showing a doubtful grid.
Will I ever have to guess?: No. Having one solution is not the only test: the solver must also reach it one row or column at a time, working only from each line's clue and the squares already settled. A grid that has one solution but can only be finished by trying a square both ways is dropped too. So every puzzle offered here can be finished by reasoning about single rows and columns, and a Hint always has a line to point at while your marks are correct.
What does the Hint button show?: It works in order. First it names any row or column whose marks cannot fit its clue at all, which also shows as a red clue. Next it names a row holding a mark that does not match the solution. Otherwise it picks the row or column where the clue and your marks settle the most unmarked squares, outlines those squares on the board and says in words which ones to fill and which to cross. It never places a mark for you. Each hint adds one to the hint count, which shows beside your progress, and a solved puzzle keeps its count in the list of recent puzzles.
Can I print a nonogram?: Yes. Print sends a sheet with the clue grid and empty squares, headed with the size and seed, plus a short note on the rules. Tick the box to add the answer on a second page. The squares print at 14 mm on a 5 x 5 board and shrink to 9 mm on a 15 x 15, so the larger grids still fit with their clues on one page. Copy puts the same clues and grid on the clipboard as text, with any marks you have made.
What is the seed, and can I play the same puzzle again?: The seed is a whole number from 1 to 999999 that decides the picture. The generator draws its random numbers from a fixed formula seeded by the size and the seed, so the same pair gives the same puzzle on any device. The size and seed of the puzzle on the board are shown above it and in the Seed box. To open a puzzle again, choose its size, type its seed and press Play seed. New puzzle picks a random seed at the chosen size.
Is my progress saved?: Yes, in this browser only. The puzzle on the board, your marks, its hint count, the tool you chose, and up to 11 earlier puzzles you had started are kept, so a reload or a later visit opens where you left off. Resume reopens an unfinished puzzle with its marks, and Play again reopens a solved one on an empty grid. Undo reaches back through up to 400 strokes made since the puzzle on the board was opened in this visit. Nothing is uploaded, and the Start over button at the top of the page forgets all of it. If the browser refuses storage, the page says so and the puzzle still plays.

Every puzzle is generated here from an original seeded pattern, never copied from a puzzle pack. A grid is offered only when the solver finds exactly one solution and reaches it one row or column at a time; one with two solutions, one that needs a guess, or one the search cannot settle within its step limit is dropped. The clues are the exact run lengths of the filled squares, and there is no difficulty rating, because none is measured.