How to Solve Nonograms

A comprehensive guide to mastering the art of nonogram puzzles

What is a Nonogram?

A nonogram (also known as Picross, Griddlers, or Hanjie) is a logic puzzle where you reveal a hidden picture by filling in cells on a grid using numerical clues. These clues, displayed along the sides of the grid, indicate how many consecutive filled squares appear in each row and column.

Unlike Sudoku, which uses numbers:

  • ✓ Nonograms create pictures through logical deduction
  • ✓ No guessing is required in well-designed puzzles
  • ✓ Every step can be solved through pure logic
  • ✓ The solution reveals a meaningful image

Basic Rules

  • 1 Numbers on the left indicate filled cells in each row
  • 2 Numbers at the top indicate filled cells in each column
  • 3 Numbers represent consecutive filled squares in order
  • 4 Groups must have at least one empty cell between them

Example:

Nonogram example grid

Step-by-Step Guide for Beginners

🎯

Start with the largest numbers

Look for rows or columns with large numbers that leave little room for variation.

📏

Look for full rows/columns

If a number equals the grid size, that entire row/column must be filled.

🔍

Find overlaps

When a number is large enough, some cells must be filled regardless of the exact position.

Use crosses (X)

Mark cells that must be empty with X to help visualize the puzzle better.

🔄

Cross-reference

Compare information from rows and columns to confirm cell states.

Understanding the Logic

Nonograms are pure logic puzzles based on simple rules but capable of complex deductions. Success comes from understanding and applying these core principles:

Basic Techniques

  • Determining where filled cells must be
  • Identifying mandatory empty cells
  • Using completed sections as anchors

Advanced Strategies

  • Edge case analysis
  • Pattern recognition
  • Complex deduction chains

Frequently Asked Questions

Can a nonogram be unsolvable?

A properly designed nonogram should have exactly one solution and be solvable through logic alone. However, poorly designed puzzles might have multiple solutions or require guessing.

Do nonograms require guessing?

No, well-designed nonograms never require guessing. Every step should be deducible through logic. If you find yourself guessing, try looking for more logical steps you might have missed.

What makes a nonogram difficult?

Grid Size

Larger grids are generally more challenging

Cell Distribution

Complex patterns increase difficulty

Logic Complexity

Advanced deduction steps required

Solution Path

Number of steps to completion

Difficulty Levels

Beginner (5x5, 8x8)

Simple patterns, straightforward logic

Easy (10x10)

Basic techniques required

Medium (15x15)

More complex deductions needed

Hard (20x20)

Advanced techniques required

Expert (25x25 and larger)

Complex logic chains, requires significant experience

Tips for Success

Mark Empty Cells

Always mark cells you know must be empty with an X

📊

Work Systematically

Start with larger numbers and work your way down

✏️

Use Markers

Right-click to mark uncertain cells

Double Check

Regularly verify your progress

🔍

Look for Patterns

Find rows or columns with partial information

🎯

Practice

Start with smaller grids before attempting larger ones