Play Binairo online
In Binairo online you fill a grid with zeros and ones until all three rules hold. Every puzzle has exactly one solution. Pick a size (6 × 6 to 10 × 10) and a level; a hint names not only the right cell but also the reason. No sign-up, works on a phone.
Source: Wikipedia – Takuzu. Updated: .
How it is calculated
In short: Binairo (also called Takuzu or binary puzzle) is a logic puzzle with just two digits. You do not need to calculate, only to deduce: every cell can be derived from the rules and you never have to guess.
The three rules
- Never more than two identical digits directly in a row, horizontally or vertically.
- Every row and column contains equally many zeros and ones (four each on an 8 × 8 grid).
- No two rows and no two columns may be identical.
How to play
Tap an empty cell: it changes from empty to 0, to 1 and back to empty. Given cells are shaded and cannot be changed. Rule violations get a red outline while the option is on. “Check” compares with the solution, “Undo” takes back entries.
Typical deductions
- Two identical side by side: the other digit goes on both sides (“00” becomes “1001”).
- A gap between two identical: the middle is the other digit (“1_1” becomes “101”).
- Half reached: if a row already has all allowed zeros, the remaining cells are ones.
- No duplicate rows: if an almost complete row has one gap and otherwise matches a finished row, the gap must differ.
Hints and levels
The hint shows a cell that follows by necessity and names the rule behind it, so you learn the deductions. Every puzzle has exactly one solution; the level decides how many cells are given.
Frequently asked questions
How does Binairo work?
You fill a grid with 0 and 1. Never three identical digits in a row, equally many zeros and ones in every row and column, and no two identical rows or columns.
What is the difference between Binairo and Takuzu?
It is the same puzzle under different names. “Binary puzzle” and “binary sudoku” mean it too.
Do you have to guess in Binairo?
No. Every puzzle here has exactly one solution and can be solved by logic. The hint gives the deduction if you get stuck.
How do I start?
Look for two identical digits side by side and for gaps between two identical ones. Then check rows and columns where one digit has already reached half.
Is my progress saved?
No. The game runs entirely in your browser; no data is stored or sent.
Sources and legal basis
As of: · Editorial policy
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