Binairo guide
How to play Binairo (Takuzu)
Binairo gives you a grid, two symbols and three rules. The clues are enough to finish the grid without guessing. Pairs and line balance force most early moves; uniqueness matters later.
What is a Binairo puzzle?
Binairo, Binario and Takuzu are different names for the same binary logic puzzle. Fill every cell with one of two symbols, then check each row and column against the rules below.
Some versions use 0 and 1 and are called a Binary Puzzle or Binary Sudoku. Bidoku uses X and O. Only the notation changes. A well-made puzzle has one solution. The existing clues determine every placement.
The three rules of Binairo
No three identical symbols
No row or column can contain XXX or OOO.
Equal numbers of X and O
A finished row or column has the same number of Xs and Os.
No duplicate lines
Two completed rows cannot match. Neither can two completed columns.
Common Binairo deductions
Start with cells that have only one legal value. The same deductions apply in rows and columns, whether the puzzle uses X/O or 0/1.
Close a pair
If two matching symbols touch, place the other symbol on each open side. A third match would break the first rule.
Fill a sandwich
A gap between two matching symbols must contain the opposite symbol.
Complete the balance
A 6-cell line needs three Xs and three Os. Once three of either symbol are present, fill every remaining cell with the other.
Protect uniqueness
If a line has two blanks and all its other cells match a completed line, fill the gaps in the opposite order. Otherwise the two lines would be identical.
How to solve your first Binary Puzzle
- Check every row and column for XX, OO, X_X and O_O.
- Count both symbols. When a line already contains half Xs or half Os, fill its empty cells with the other symbol.
- After each move, scan the crossing line again. One placement often creates the next forced cell.
- Compare similar lines. Use the no-duplicates rule when two rows or columns are close to matching.
- If neither value is forced, move on. Guessing tends to hide mistakes rather than help.
Bidoku marks broken rules and can show a logical hint for the next forced cell. A smaller grid makes these patterns easier to spot. Larger boards use the same rules.
Import and solve a Binairo puzzle from a photo
If your Binary Puzzle is in a book, newspaper or another app, you can import a photo or screenshot into Bidoku. Crop the image to the grid, set the number of rows and columns, and confirm the selection. Bidoku turns it into an interactive board. You can finish it yourself or ask for hints.
Binairo and Takuzu FAQ
Are Binairo, Binario and Takuzu the same puzzle?
Yes. They are different names for the same binary logic puzzle. Some games use 0 and 1; Bidoku uses X and O.
What are the three rules of Binairo?
Every row and column must contain equal numbers of both symbols, three identical symbols may not appear consecutively, and completed rows and columns must all be unique.
Do you need to guess in Binairo?
A well-made puzzle has one solution and enough clues to deduce every move. If a cell is uncertain, leave it and inspect another row or column.
Is a Binary Puzzle the same as Sudoku?
No. Both are grid-based logic games, but Sudoku uses digits and box constraints. A Binary Puzzle uses only two symbols and relies on balance, adjacency and uniqueness rules.
Can I play Binairo online for free?
Yes. Bidoku runs in a web browser. It is free and does not require an installation.
Can Bidoku solve a Takuzu puzzle from a picture?
Yes. Import a clear photo or screenshot, crop it to the grid and set the number of rows and columns. Bidoku turns the image into an interactive puzzle.
Play Binairo in your browser
Open Bidoku to start a new grid or import a puzzle you already have.
Open the free Binairo game