TWO DIGITS. A LITTLE DEDUCTION.
Binary Puzzle.
Balance every line.
Let the zeros and ones fall into place.
Puzzle 1 / 24
0 / 27 entered
Choose an empty square. Tap to cycle blank, 0, 1, then blank again.
Fill each row and column with equal numbers of 0s and 1s. Never place three matching numbers in a row. Completed rows must differ from each other, and completed columns must differ too.
Keyboard, touch & fixed numbers
Tap an editable square to cycle blank → 0 → 1 → blank. The bold, underlined numbers are fixed givens; they can receive focus but cannot be changed. Your entries use regular text without an underline.
Tab to the board, then use arrow keys to select any square. Type 0 or 1 to enter a value; Delete or Backspace clears it. Enter or Space cycles a selected square. Browser shortcuts, scrolling and pinch zoom remain available.
Wrong entries stay in your draft. Check reports a contradiction without changing numbers; Hint explains a forced next entry and waits for Apply hint. Undo applies to changes in this tab. After a reload, your saved draft is the new undo starting point.
24 original puzzles on 6×6 and 8×8 grids. Every puzzle is checked for one solution and a complete route using our supported deduction rules. Sizes describe the boards; they are not measured difficulty ratings. Your progress stays in this browser.
ALSO CALLED TAKUZU
How to play Binary Puzzle
Fill each empty square with 0 or 1. Printed digits stay fixed. Every row and every column must follow all three rules.
- Keep the balance. Each line has an equal number of zeros and ones: three of each on a 6×6 board, or four of each on an 8×8 board.
- Avoid triples. Three equal digits cannot sit next to each other horizontally or vertically. Diagonals do not count.
- Make each line distinct. No two completed rows may be identical; no two completed columns may be identical. A row may match a column.
A CERTAIN NEXT DIGIT
Start with pairs and balance
Read a row or column as a whole. A digit can fit its nearby neighbors and still leave too many zeros or a repeated line later.
- Break a triple. In
0 0 _, the blank is 1. In1 _ 1, it is 0. Check both directions. - Finish the balance. When a 6-cell row already has three zeros, all its remaining spaces must be ones.
- Compare completed lines. A nearly finished row must differ from every completed row. Check columns in the same way. Hint compares the remaining legal patterns and explains one forced digit.
ROOM TO WORK IT OUT
Before the next zero or one.
Are Binary Puzzle and Takuzu the same game?
On Brainfold, both names refer to this game with equal counts, no triples and distinct rows and columns. This page uses zeros and ones; a blank square is neither digit.
How do I enter or erase a digit?
Tap an editable square to cycle blank, 0, 1 and blank again. You can also select it and use the 0, 1 or Clear controls. Arrow keys move focus; 0 and 1 enter digits, and Backspace or Delete clears a square. Printed givens cannot be changed.
Will Check change my board?
No. Check tests whether your current entries can lead to a complete valid board. Wrong entries remain available to undo or erase. If the search reaches its limit, the result stays unknown. A hint shows one explained step and waits for you to apply it.
Where do these puzzles come from?
They were generated for Brainfold, filtered for a unique solution and supported logical deductions, and checked for repeated layouts under rotations, reflections and a swap of 0 and 1. We do not copy other sites’ boards or claim that a matching arrangement cannot exist elsewhere. You can read the standard rules at BinaryPuzzle.com.
Is my progress shared between devices?
Progress is saved only in this browser. Browsing another puzzle does not replace your saved board; making a board change saves that puzzle. Undo history lasts for the current session. Restart clears your entries while keeping your completion record.