Free
1,200+ Puzzles
6×6, 8×8, 10×10 & 12×12
3 Difficulty Levels
New puzzle every day — over 1200 logic puzzles in every size and difficulty.
Every day, a new free binary puzzle appears on Logicus, ready to be solved online. The daily puzzle is challenging, but in addition, there are 1200 other binary logic puzzles available in 6×6, 8×8, 10×10, and 12×12 grids, across three difficulty levels.
Logicus is a Progressive Web App — no app store required. Play at app.logicus.be and add it to your home screen for quick, app-like access.
A binary puzzle is a logic puzzle where you fill a rectangular grid with two symbols, usually 0s and 1s, following three simple rules.
Each row and column must contain an equal number of 0s and 1s, no more than two identical numbers may sit next to each other, and no two rows or columns can be identical. Like Sudoku, each puzzle starts with a few cells already filled in.
Binary puzzles are popular worldwide under a handful of different names. If you searched for one of these, you're in the right place.
The name most commonly used in Belgium and the Netherlands.
The name this puzzle usually goes by in France.
Well-known names for the same puzzle in German-speaking countries.
A common English-language name, sometimes seen in puzzle magazines.
A nickname that stuck because the rules feel familiar to Sudoku fans.
Other names you'll come across in puzzle books and apps.
Each row and column must contain an equal number of 0s and 1s.
No more than two identical numbers may be adjacent (vertically or horizontally).
Each row and column must be unique within the grid.
Look for double numbers next to or below each other. The cells next to doubles can only contain the opposite number.
If there's a free space between two identical numbers, it must always be the opposite number.
There must be an equal amount of 0's and 1's in a row or column. Count! If there are already enough 0s, the remaining cells must be 1s (and vice versa).
Each row and column must be unique. If you're only missing a few cells look for other rows or columns that are similar and enter the opposite numbers.
Testing for rule breaks involves mentally placing the last 0 or 1 in a row or column and checking if it forces the remaining cells to violate the rules, allowing you to deduce the opposite number instead.
Each puzzle has a unique solution. Using the rules above you should never have to guess.
Printable Logicus puzzle books are available in the Ko-fi shop — 100 puzzles per book, solutions included in the back, and every puzzle has its own QR code linking straight to that exact puzzle online.
Not quite, though they're cousins in the logic-puzzle family. Sudoku uses digits 1-9 across rows, columns and boxes. A binary puzzle only uses 0s and 1s, has no boxes, and instead relies on three rules: equal counts per row/column, no more than two identical numbers in a row, and no two rows or columns alike.
Logicus has a new free puzzle every day, plus a library of over 1200 additional puzzles across different grid sizes and difficulty levels.
Yes, completely free. There are no paywalls, no ads-gated puzzles, and no account required.
No ads and no invasive tracking. Logicus uses Umami, a privacy-friendly analytics tool that doesn't use cookies and can't identify who you are — just a rough sense of how many people visit.
No. Logicus runs directly in your browser at app.logicus.be. You can optionally install it as a Progressive Web App for quick, app-like access from your home screen.
Yes. Your progress and settings are saved locally in your own browser, so you can pick up where you left off — no account needed.
Puzzles come in 6×6, 8×8, 10×10, and 12×12 grids, across three difficulty levels, so there's a fitting challenge whether you're just starting out or want something tougher.
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