How to play Nonogram: a beginner's guide

Daily Nonogram (also called Picross, Griddler, or Hanjie) is a logic puzzle played on a small square grid. Every row and every column has a list of numbers beside it. Those numbers tell you the runs of filled cells on that line, in order. Your job is to work out which cells to fill so that every row and every column matches its clues. Fill them all correctly and the puzzle locks in automatically.

What the clues mean

A clue like 3 1 2 on a row says: somewhere in that row, reading left to right, there is a run of three filled cells, then at least one empty cell, then a single filled cell, then at least one empty cell, then a run of two filled cells. Column clues work the same way, reading top to bottom.

Two important details follow from that:

• Runs never touch. A gap of at least one empty cell separates every run in the clue — otherwise they'd merge into a single, longer run.
• A clue of 0 means the line is empty. No filled cells anywhere on that row or column.

Technique 1: the line is tight

Add up the numbers in a clue and the gaps between them. If a row is 10 cells wide and the clue is 4 5, the minimum length of the pattern is 4 + 1 + 5 = 10 — it takes up the whole row. That means there's only one way to place it: four filled, one empty, five filled. You've solved the line from nothing but arithmetic.

Even when the clue isn't that tight, you can often fill themiddle of a long run. A clue of 7 on a 10-cell row can start anywhere from column 1 to column 4, so the cells that are inside the run no matter where it starts (columns 4 through 7) must be filled. This “overlap” technique is the single most useful move in nonograms.

Technique 2: cross-reference with the other axis

The grid is solved the moment both rows and columns match their clues — so every cell answers to two clues at once. When you fill a cell from a row clue, look at that column's clue too. Sometimes the column tells you the cell below or above must also be filled, which feeds straight back into the row.

This bouncing back and forth is most of what solving a nonogram feels like. Every new filled cell is a fresh constraint on the other axis, and many moves that look invisible on the row side become obvious as soon as you check the column.

Marking cells you're sure are empty

In a pencil-and-paper nonogram, experienced solvers mark empty cells with a small dot or X. It's just as important as filling cells — knowing a cell is empty often pushes a run in one direction and unlocks the next deduction. The on-screen puzzle only tracks filled cells, so keep mental track of the cells you've ruled out.

When the puzzle solves

You don't press a submit button. The moment every row reads the runs in its clue and every column does the same, the puzzle auto-completes. There's exactly one valid solution for each Daily Nonogram — if your grid satisfies the clues, it's right.

Start with the tightest clues first — the ones where the numbers plus the gaps nearly fill the line. Those are the footholds that make the rest of the grid fall into place.