Binairo

How to play

• Fill every cell with a sun or a moon.
• Never three of the same in a row, across or down.
• Every row and every column has as many suns as moons.
• No row may be the same as another row, and no column the same as another column.

Using the game

• Tap an empty cell: once for a sun, twice for a moon and a third time to empty it.
• With a keyboard: move with the arrows and type 1 for a sun, 2 for a moon.
• Cells that break a rule turn red.

Difficulty

• Easy: 6 × 6 cells. Pairs, gaps and counting take you all the way. 2–5 minutes.
• Medium: 8 × 8 cells. Sometimes you need to think through the ways a row can be filled. 5–15 minutes.
• Hard: 10 × 10 cells and fewer given cells. Sometimes the rule that two rows may not be equal decides it. 15–30 minutes.

Keyboard

• Arrow keys: move between cells
• Space / Enter: empty → sun → moon → empty
• 1 / S: sun
• 2 / M: moon
• 0 / Backspace / Delete: empty the cell
• Ctrl + Z or U: undo
• H: hint
• P: pause

Questions

Where does the puzzle come from?
Binairo (also called Takuzu or binary puzzle) was created by Peter De Schepper and Frank Coussement. This version and its puzzle generator are our own.

Is there always a unique solution?
Yes. Every puzzle is made here and checked so that it can be solved by logic all the way. That means there is only one solution.

Is my puzzle saved?
Yes, in this browser. You can close the page and continue later.

Can I play the same puzzle as a friend?
Yes. Tap the puzzle code and send the link.

Questions and answers

More pen and paper

• Block Puzzle
• Codebreaker
• Nonogram
• Queens
• Sonar
• Sudoku
• Tectonic
• Word Chase