Play a 6x6 Hard Binary Puzzle

This board is generated from a replayable seed and checked for one valid solution before it reaches your screen.

Practice puzzle6x6 Hard

0:0050% filled

Tap a cell to cycle it, or use arrow keys with 0, 1, Backspace, and Delete.

Binary Puzzle · Paper edition

6×6 Hard puzzle

Fill every empty square with either 0 or 1.

Practice puzzleOne unique solution

NameDateTime

101001100101011010

Three rules

Keep it balancedEvery row and column contains 3 zeros and 3 ones.
Avoid triplesNo more than two identical numbers can be next to each other.
Make every line uniqueNo two rows and no two columns can be exactly alike.

Balance every lineEach row and column uses the same number of 0s and 1s.

Never make threeThree matching values cannot touch in a horizontal or vertical run.

Keep lines uniqueNo completed row or column can repeat another line.

Read all rules

How to approach Hard at 6x6

Start with no-three patterns, count both values, then compare the valid line patterns. Return to simple rules after every new entry.

Clues18 fixed cells start this board.

DepthThe hardest expected rule is uniqueness.

Proof20 unique-solution checks shaped the puzzle.

Play a 6x6 Hard Binary Puzzle

This board is generated from a replayable seed and checked for one valid solution before it reaches your screen.

Practice puzzle6x6 Hard

0:0050% filled

Tap a cell to cycle it, or use arrow keys with 0, 1, Backspace, and Delete.

Binary Puzzle · Paper edition

6×6 Hard puzzle

Fill every empty square with either 0 or 1.

Practice puzzleOne unique solution

NameDateTime

101001100101011010

Three rules

Keep it balancedEvery row and column contains 3 zeros and 3 ones.
Avoid triplesNo more than two identical numbers can be next to each other.
Make every line uniqueNo two rows and no two columns can be exactly alike.

Balance every lineEach row and column uses the same number of 0s and 1s.

Never make threeThree matching values cannot touch in a horizontal or vertical run.

Keep lines uniqueNo completed row or column can repeat another line.

Read all rules

How to approach Hard at 6x6

Start with no-three patterns, count both values, then compare the valid line patterns. Return to simple rules after every new entry.

Clues18 fixed cells start this board.

DepthThe hardest expected rule is uniqueness.

Proof20 unique-solution checks shaped the puzzle.

Play a 6x6 Hard Binary Puzzle

How to approach Hard at 6x6

Keep the next challenge close

Play a 6x6 Hard Binary Puzzle

How to approach Hard at 6x6

Keep the next challenge close