How to solve Nonogram

How to solve nonograms: techniques that work

The overlap technique solves most cells and never guesses. Take a clue and imagine its block pushed as far left as possible, then as far right as possible: every cell covered in both scenarios is certainly filled. A 4-clue in a 5-wide row overlaps on three cells; an 8-clue in a 10-wide row overlaps on six. Do this for every long clue before anything else.

Mark empties as aggressively as you mark fills. When a clue is satisfied, ✕ out the rest of its line — those ✕ marks are what unlock the crossing lines. A nonogram is solved by bouncing between rows and columns, each pass feeding the next; a line you "finished" still helps perpendicular lines through its ✕ marks.

Anchor from the edges. A filled cell touching the border pins its whole block: if the first row clue is 3 and the corner cell is filled, cells two and three follow immediately and cell four is empty. Edge anchors plus overlaps typically crack the border, and the interior follows.

Common mistakes

Reading "2 1" as one block: it's two separate blocks — a pair, at least one empty cell, then a single — in that exact order. Order matters; blocks never swap.

Guessing on a 50/50 cell. Unlike print nonograms of dubious provenance, every board here has a unique solution reachable by logic, so an apparent coin-flip always means an overlap or a cross-reference you haven't used yet.

From easy to hard

5×5 boards teach the vocabulary; 10×10 boards demand disciplined ✕ marking and multi-line bookkeeping. The picture emerging is your progress bar — nonograms (also known as Picross, Hanjie or Griddlers) reward slow, certain play over fast guesses.