Nonogram (Picross)

A Nonogram is a picture logic puzzle in which the numbers beside each row and column give the lengths of the filled runs in that line, in order, with at least one empty cell between consecutive runs — shade the cells those clues demand and a hidden picture emerges. It is played on a blank grid, and around the grid sit the clues: a string of numbers beside every row and above every column. Those numbers give the lengths of the filled runs in that line, written in the order they appear, and there must be at least one empty cell between consecutive runs. Because the finished grid reveals an image, the puzzle is also called a picture cross.

How do you read a Nonogram clue?

Reading a clue is the whole skill. A row marked “4 2” means: somewhere along that row there is a block of four filled cells, then a gap of one or more empty cells, then a block of two filled cells, in that order from left to right. The clue tells you the sizes and the sequence, but not where the runs start — that is what you deduce. A clue of 0 (or a blank) means the line is completely empty.

The three cell states

Every cell ends up in one of three states, and tapping a cell cycles through them. Knowing what each means keeps your reasoning honest:

Why is a Nonogram solvable by pure logic?

Crucially, the row clues and the column clues describe the same grid from two directions, and the two must agree everywhere. That double constraint is what makes a Nonogram solvable by pure logic: a cell is filled only if every consistent reading of its row and its column agrees it is filled, and empty only if they agree it is empty. Every board on this page has exactly one solution reachable by reasoning alone — you never have to guess and hope the picture works out.

Solve a Nonogram by applying a few reliable techniques in order — overlapping long runs, completing forced lines, marking proven-empty cells with ✕, anchoring runs to the edges, and cross-referencing rows against columns — always working the most-constrained lines first. Good Picross solving works from the lines that give away the most to the lines that give away the least. These are the core nonogram tips:

• Overlapping (forcing) on long runs. Slide a run as far left as it will go, then as far right; any cell covered by both extremes must be filled. A clue of 4 in a width-5 line, for example, always overlaps in the middle three cells whichever way it sits.
• Complete the obvious lines first. If a clue’s runs plus their minimum gaps add up to the full width, the whole line is forced — fill the runs and mark the gaps. A clue of “2 2” in a width-5 row is the classic case.
• Use the ✕ marks. Tap a cell to a second state — an ✕ for “definitely empty”. Marking cells you have proved blank is just as valuable as filling cells, because it pins down where the next run can and cannot reach.
• Work the edges and anchors. A filled cell touching an edge anchors the first run to that corner: if the leading clue is 3 and the end cell is filled, the next two cells along must be filled too.
• Cross-reference rows and columns. Every cell you fill or ✕ in a row is new information for its column, and vice versa. Bounce between the two — a deduction in one direction almost always unlocks one in the other.

Which lines should you solve first?

Build the habit of working the most-constrained lines first — the longest clues, the fullest lines, the edges — because that is where cells are forced. After each move, re-scan the rows and columns that crossed it. And never guess: on a proper Nonogram there is always a next cell you can prove.

A five-cell row with the clue 4 forces its middle three cells, because the run can only sit flush left (cells 1–4) or flush right (cells 2–5) and cells 2, 3 and 4 are filled in both — the overlapping technique in miniature. A line or two shows how the logic clicks into place. Overlay those two positions and you can shade the middle three straight away, even though you do not yet know which end is empty.

When is a whole line forced?

Now suppose the same row read “3 1” instead. The minimum that clue can occupy is three filled, one gap, one filled — five cells, exactly the width. The line is forced: cells 1–3 filled, cell 4 an ✕, cell 5 filled, with no other arrangement possible. Whenever a clue’s runs plus their compulsory single-cell gaps equal the length of the line, you can complete it outright.

How the picture builds from there

From there the picture builds itself. Each cell you fill is a clue for its column; each ✕ you place narrows where that column’s runs can fall. Keep alternating between rows and columns, always taking the forced move first, and the hidden image resolves one deduction at a time — never a guess in sight.

This page offers a 5×5 grid as a friendly introduction and an 8×8 grid as a meatier solve with longer clues, more lines to juggle and a more detailed picture at the end. The smaller board is small enough to take in at a glance, and a perfect place to learn how the overlapping and forcing tricks feel.

Difficulty in a Nonogram does not come only from size. It comes from how tightly the clues constrain the grid: a board packed with long runs and full lines almost solves itself, while one with lots of short, scattered runs forces you to lean harder on cross-referencing and ✕ marks before a single cell is certain. As the grid grows, those interactions multiply, and the satisfying chains of deduction get longer.

Tap New for a fresh picture at either size whenever you like, or play the shared Daily to solve the very same board as everyone else that day — a small, repeatable ritual and an easy way to compare notes.

Nonogram, Picross, Griddlers, Hanjie, Pic-a-Pix, Paint by Numbers and Picture Cross are all names for the same picture-shading puzzle, which was popularised independently around the world. Each label describes the identical idea:

• Nonogram — the name used in much of the puzzle world, coined from its Japanese inventor.
• Picross — short for “picture crossword”, the name Nintendo made famous in its video games, and the term most players know today.
• Griddlers and Hanjie — the names British newspapers ran them under.
• Pic-a-Pix, Paint by Numbers and Picture Cross — further aliases from puzzle magazines and apps.

Whatever the label, the idea is the same: a picture puzzle solved by shading cells, not by writing numbers into them. That makes it a close cousin of the other shading and region puzzles in this collection — try Nurikabe, where you shade a connected “sea” around numbered islands, or Hitori, where you shade out duplicate numbers — both of which reward the same patient, cell-by-cell reasoning.

The key Nonogram terms are clue (run), line, run (block), gap, fill, ✕ mark and solution — a handful of words that turn up in every Nonogram guide. You do not strictly need them to play, but they make any strategy guide far easier to follow:

• Clue (run) — a number beside a line, giving the length of one block of consecutive filled cells.
• Line — a single row or column, described by its own list of clues.
• Run (block) — an unbroken group of filled cells matching one clue number.
• Gap — the empty cell, or cells, that must separate one run from the next in the same line.
• Fill — to shade a cell you have proved is part of a run.
• ✕ mark — a “definitely empty” marker you place on a cell you have proved is blank; an aid for you, it does not affect the answer.
• Solution (picture) — the single shaded pattern, and the image, that satisfies every row and column clue at once.

You do not need the vocabulary to play — just tap to fill — but it makes any strategy guide far easier to follow.

The most common Nonogram mistakes are guessing where a run sits, neglecting the ✕ marks, forgetting the compulsory gaps between runs, working in only one direction, and reading clues out of order. Most Nonogram tangles come from a few avoidable habits:

• Guessing where a run sits. Filling cells on a hunch can quietly contradict a crossing line and corrupt the picture for dozens of moves. There is always a forced cell — find it instead.
• Not using the ✕ marks. Players who only ever fill cells throw away half the information. Marking proven-empty cells is what reveals where the next run must go.
• Forgetting the gaps. A clue of “2 2” needs at least one empty cell between the blocks; squeezing them together is a classic slip.
• Working only in one direction. Solve rows in isolation and you stall fast. Every fill and ✕ feeds the crossing column — keep bouncing between the two.
• Reading clues out of order. The numbers always run left-to-right (or top-to-bottom); the first clue is the first run, not whichever block you spot first.

The Nonogram was born in Japan in 1987, invented at much the same time by graphics editor Non Ishida — whose first name gave the puzzle its word — and puzzle designer Tetsuya Nishio, who arrived at a similar picture puzzle independently. Two people thus reached the idea almost simultaneously, and the puzzle has carried Ishida’s name ever since.

How did the Nonogram get its many names?

From Japan the puzzle spread worldwide through newspapers. In Britain it appeared under names coined for local readers — James Dalgety gave it the name Hanjie, while The Sunday Telegraph ran it as Griddlers. The name most players know, though, arrived through video games: from 1995 Nintendo popularised the puzzle as Picross, and a long line of releases carried it to a global audience.

Today the very same puzzle travels under all of those names — Nonogram, Picross, Griddlers, Hanjie, Pic-a-Pix, Paint by Numbers and Picture Cross — but the appeal has never changed: a grid of numbers that, solved with nothing but logic, quietly turns into a picture.