Futoshiki (BrainBashers)

About Futoshiki (BrainBashers)

Futoshiki is a Japanese number puzzle, and BrainBashers posts a fresh set of them every day. The board is a square grid, usually with a couple of digits already given and inequality signs placed between neighbouring squares. You fill in the numbers so that each row and each column contains 1 up to the grid size exactly once, and every sign is respected: the narrow end always points to the smaller number.

The daily set has 4x4, 5x5, 6x6 and 7x7 grids, each at Easy and Hard, and a 9x9 grid as the weekly special. Each opens on its own dated page with Kevin Stone's copyright, and the usual BrainBashers tools: check, pencil marks, answer, print and restart, an option to show mistakes when checking and an optional clock. A help page walks through a solve.

All daily puzzles on the site change at midnight GMT, with a setting for your own time zone, and the date list reaches back a few weeks. The site carries no adverts and needs no account.

It suits sudoku players who want something smaller and quicker, and the chains of signs make for satisfying deductions on the larger grids.

How to play Futoshiki (BrainBashers)

1. Open the Daily Futoshiki page and choose today's size and level.
2. Fill each row and column with the numbers 1 to the grid size, each exactly once.
3. Make every < or > sign true: it always points towards the smaller of the two numbers.
4. Use pencil marks to track candidates and press check when the grid is full.
5. Reveal the answer if needed; a new set arrives after midnight GMT.

Tips

• A square with a sign pointing into it from both sides cannot hold 1; one with signs pointing away cannot hold the largest number.
• Follow chains of signs: a run of three rising signs pushes the first square down to small values and the last one up.
• Look for rows where a number has only one legal place once the signs are applied.
• On the Hard grids, write full pencil marks early; they make the eliminations visible.

Questions