What is Binary, Takuzu or Binairo?
Binary is a logic puzzle played with only two symbols: 0 and 1. It is also known as Takuzu, Binairo, Binero and 0h h1, but the core rules are the same across the names.
The aim is to complete the grid so every row and column is balanced, no row or column contains three equal digits in a row, and no two rows or columns are identical. This free Binary puzzle game creates multiple grid sizes and difficulties, then checks each puzzle for one unique solution before it appears.
- Fill every empty square with either 0 or 1.
- Each row and column must contain the same number of zeros and ones.
- Three matching digits cannot appear consecutively in any row or column.
- No two completed rows can be identical, and no two completed columns can be identical.
- Every online Binary puzzle is tested by a solver for a unique solution.
How to play Binary online
Start by scanning for pairs. If you see 00, the squares immediately before or after that pair, when they exist, must be 1. The same idea turns 11 into forced zeros.
Next, look for split pairs such as 0 _ 0 or 1 _ 1. The middle square must be the opposite digit. The Check button flags mistakes without revealing the full answer, and Hint gives one square when you want a nudge.
- Use the 0 and 1 buttons, or click a cell to cycle through possible entries.
- Watch the row and column counts as they approach an equal number of zeros and ones.
- Complete forced triples first because they are the clearest Binary clues.
- Compare nearly complete rows and columns to avoid duplicates.
- Use Undo, Reset or Solution when you want to practise a different solving path.
Binary grid sizes and difficulties
Small 6x6 Binary puzzles are friendly for learning the rules. The 8x8 size is a quick everyday Takuzu puzzle, while 10x10 and 12x12 grids create longer chains of balance and uniqueness logic.
Easy puzzles leave more clues and more immediate pair patterns. Medium puzzles remove more givens, so row counts and column counts matter earlier. Hard Binary puzzles rely more on comparing possible duplicate rows and columns.
- 6x6 Binary is a compact beginner grid.
- 8x8 Binary is the default balanced size.
- 10x10 and 12x12 Binary are stronger strategy challenges.
- Easy, medium and hard each generate a fresh puzzle.
- A puzzle is kept only when the internal solver finds exactly one solution.
Binary puzzle strategy
The best Binary strategy alternates between local patterns and whole-line checks. Local patterns stop triples. Whole-line checks keep the number of zeros and ones balanced.
When a row is almost complete, count its zeros and ones. If a row already has half of one digit, every remaining square in that row must be the other digit. The same count rule works for columns.
Uniqueness is the final layer. If two rows are one move away from becoming identical, the open square may be forced to keep them different. This is often the step that turns a medium or hard Takuzu puzzle.
- 00_ and _00 force a 1; 11_ and _11 force a 0.
- 0_0 forces a 1; 1_1 forces a 0.
- A full row or column must contain half zeros and half ones.
- Completed rows and completed columns must be unique.
- If two nearly complete lines would match, place the opposite digit in the unresolved square.
Why unique Binary puzzles matter
A Binary puzzle should be solved by deduction, not by choosing between two equally valid endings. That is why this generator does more than create a valid finished grid.
After building the answer, it removes clues one at a time and runs a solver after each removal. If the puzzle would have two solutions, the clue is put back. The result is a playable Binary puzzle with only one solution.