Mosaic Puzzle Online

Mosaic is one of the classic one-player logic games in Simon Tatham's Portable Puzzle Collection. Fill in the grid given clues about number of nearby black squares.

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Preparing the game board and controls.

Game Objective

Decide whether every square is black or white. A number tells how many black squares are in that square and the ring of neighboring squares around it, including diagonal neighbors.

Fill in the grid given clues about number of nearby black squares.

How to Play

Left-click an empty square to mark it black.
Right-click an empty square to mark it white.
Click an already marked square again to cycle it between black, white, and undecided.
You can also drag with left or right mouse button to mark several squares quickly.
These puzzles reward careful deduction more than speed. Start with the most constrained clues, eliminate impossible choices step by step, and avoid guessing unless the puzzle specifically calls for it.

Beginner Tips

A 0 means the numbered square and all its neighbors are white. A 9 means the numbered square and all its neighbors are black.
If a clue already has enough black squares around it, all remaining undecided squares next to that clue must be white.
If the undecided squares are exactly enough to reach the clue number, all of them must be black.