Nonogram Guide: Clues, Marking, and Accessibility

NoCharge Nonogram (also called Picross or griddlers) presents a blank grid with row and column clues. Each clue is a sequence of numbers describing groups of consecutive filled cells. Your task is to determine which cells are filled and which are empty to reveal a hidden picture.

How to play

Select a grid size (5×5 or 10×10) and work through a curated puzzle. Each row and column has a clue. For example, a row clue of “3 1” means there are three consecutive filled cells, then at least one empty cell, then one filled cell.

Mark cells as filled (click/tap) or empty (right-click or X key). The puzzle is solved when every cell is correctly marked.

Controls at a glance

• Touch or pointer: tap to cycle through filled → empty → unknown. Right-click marks empty directly.
• Keyboard: arrows move the cursor. F marks filled. X or Space marks empty. U undoes.
• Size toggle: switch between 5×5 and 10×10 puzzles.
• Next puzzle: move to the next puzzle in the current size category.
• Show clues as text: toggle a full text listing of every clue for screen reader or text-based play.

How clue interpretation works

A clue like “2 3” on a 5-cell row means: two filled cells, at least one gap, then three filled cells. Since 2 + 1 (gap) + 3 = 6, which exceeds 5 cells, this specific example cannot fit in a 5-cell row. But on a 10-cell row, “2 3” has multiple valid placements.

Overlap technique

When a group is large enough that its possible positions overlap, the overlapping cells must be filled. For example, “4” on a 5-cell row: the group can start at position 0 or 1, so positions 1, 2, and 3 are filled regardless.

Edge anchoring

When a group fills an entire row or column, mark it completely. When a filled cell is at an edge and its group extends to that edge, mark the full group.

Strategy and patterns

Start with the most constrained lines

Rows or columns with large numbers or many groups have fewer valid placements. Solve these first to create anchor points for crossing lines.

Use marks to eliminate

Marking a cell as empty is just as informative as marking it filled. When you know a cell cannot be filled, marking it empty constrains adjacent groups.

Cross-reference rows and columns

A filled cell in a row constrains the column it belongs to, and vice versa. Work back and forth between rows and columns as new information appears.

Accessibility

Show clues as text

The “Show clues as text” button reveals a complete text listing of every row and column clue. This is useful for screen reader users who may not easily read the visual clue labels, and for anyone who prefers a text reference while solving.

Keyboard navigation

Arrow keys move a visible cursor across the grid. F marks the current cell filled, X or Space marks it empty. Every action is available without a pointer.

No fail state

There is no wrong-answer penalty, no timer, and no streak. You can mark and unmark cells freely until the puzzle is solved.

What we don’t claim

We do not claim that any specific strategy is optimal. Nonogram solving involves many valid approaches, and the best technique depends on the specific puzzle. We track your revealed puzzle count as a personal record.

Every puzzle in our library has been validated to have a unique solution.