Futoshiki
Satisfy every greater-than sign.
Futoshiki (Japanese for "inequality") is a Latin-square puzzle related to Sudoku, but instead of 3×3 boxes, some neighbouring cells carry a fixed < or > sign the finished grid has to satisfy.
Get it on
Google Play
Coming soon
App Store
How to play Futoshiki
Fill each row and column with 1 through N exactly once — like a mini Sudoku with no boxes.
Some neighbouring cells show a fixed < or > sign that the finished grid must satisfy, in addition to the row/column rule.
Tap a cell, then tap a number to fill it. A live check flags any row/column duplicate or violated inequality.
Example
A "3 > _" clue means whatever goes in the blank cell must be smaller than 3 — so 1 or 2, narrowed further by that column's other values.
Difficulty
Tips & strategy
- Chains of inequality signs (e.g. a < b < c) often pin down a small number of possibilities immediately — trace them first.
- The smallest number in the grid can never sit on the small side of a > sign pointing away from it, and vice versa for the largest number.
- Combine the Latin-square rule (no repeats in a row/column) with the inequality signs — together they eliminate options much faster than either rule alone.
Futoshiki FAQ
What does "Futoshiki" mean?+
Futoshiki (不等式) is Japanese for "inequality" — a nod to the < and > signs that are the puzzle's defining feature, layered on top of a Sudoku-like Latin square.
Is Futoshiki like Sudoku?+
It shares Sudoku's core rule — each number 1 through N appears exactly once per row and column — but has no 3×3 boxes. Instead, some cells carry inequality signs the solution must satisfy.
How do the < and > signs work?+
A sign between two neighbouring cells is permanent and always active, even before those cells are filled in. "3 > _" means the blank must hold a value smaller than 3; "_ < 3" means it must be smaller than whatever's on the other side once revealed.
What grid sizes are available?+
4×4 on Easy, 5×5 on Medium, and 6×6 on Hard — each with a unique solution guaranteed by the puzzle generator.