Dominosa Puzzle Online
Dominosa is one of the classic one-player logic games in Simon Tatham's Portable Puzzle Collection. Tile the rectangle with a full set of dominoes.
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Preparing the game board and controls.
What This Game Is
Dominosa is a self-contained logic puzzle built around one clear objective. Each new board gives you a fresh problem to solve, so it works well for quick sessions and repeated play.
Tile the rectangle with a full set of dominoes.
How to Play
Left-clicking between any two adjacent numbers places a domino covering them, or removes one if it is already present. Trying to place a domino which overlaps existing dominoes will remove the ones it overlaps. Right-clicking between two adjacent numbers draws a line between them, which you can use to remind yourself that you know those two numbers are not covered by a single domino. Right-clicking again removes the line.
Most puzzles in this collection reward deduction more than speed. Focus on the most limited choices first, use the clues to narrow the board, and avoid guesses unless the puzzle mode clearly expects them.
Beginner Tips
- Start with the area that has the strongest clue or the fewest legal options.
- Use marks, notes, or temporary indicators if the puzzle supports them.
- Try to preserve flexibility instead of committing too early when multiple moves look possible.
- If the board gets messy, restart a fresh puzzle and apply what you learned from the first run.
Official Reference
If you want the full original rule explanation, examples, and advanced options, the official manual is the best reference.
Read the official manualFrequently Asked Questions
More Logic Collection Games
Fifteen
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Filling
Mark every square with the area of its containing region.
Flip
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Flood
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Galaxies
Divide the grid into rotationally symmetric regions each centred on a dot.
Guess
Guess the hidden combination of colours.
Inertia
Collect all the gems without running into any of the mines.
Keen
Complete the latin square in accordance with the arithmetic clues.