Everything in GridDay

Refined puzzles, thoughtful details.

Five games in one

Sudoku, Killer Sudoku, Kakuro, Calcudoku, and Futoshiki — one polished app.

A new daily challenge

Every day brings a fresh daily for each game, at a difficulty that rotates through the week.

Hints that teach

Stuck? A smart hint shows the technique and the reasoning — not just the answer.

Your stats, your device

Best times, streaks, and achievements tracked locally. No account needed.

Achievements

Goals to chase across every game and difficulty.

Play anywhere

Free in your browser, or get the full app on iOS and Android.