Futoshiki
Each digit appears once in every row and column. The signs between squares show which number is larger. Look for long chains of inequalities first.
The free puzzle section
Four ways to think around a corner.
80 free logic squares across four levels. The rules change. The pleasure of the next certain step stays.
Variant
Level
Puzzle
Loading puzzle.
With a keyboard: enter digits · Shift + digit for notes · arrow keys to move · Backspace to clear.
The rules, briefly
Skyscrapers
Each digit is a building height and appears once per row and column. An edge clue tells you how many buildings are visible from that direction. Taller buildings hide shorter ones.
Magic Square
Place every number from 1 to 9 or 1 to 16 exactly once. Every row, column and both diagonals must add up to the same sum.
Calcudoku
Each digit appears once in every row and column. A cage must reach its target using the operation shown. Numbers can repeat inside a cage as long as the rows and columns allow it.
Good to know
Are the browser puzzles really free?
Yes. All 60 Sudoku and 80 logic squares can be played without a purchase or an account. The apps are a separate offer on the App Store.
What is different in the apps?
The browser contains a fixed selection and can reveal cells. Sudoku Pro and Quadrivium generate new puzzles and use their hints to explain the next logical step.
Can I play on my phone?
Yes. Tap a square and use the number buttons below the board. A larger screen is comfortable for the big Samurai grid.