A calm, free daily sudoku you play in your browser.
Gridmark is a calm, free sudoku you play in your browser — no account, no app, nothing to install. Fill the 9×9 grid so every row, column, and 3×3 box contains the digits 1 to 9 exactly once.
Choose Easy, Medium, Hard, or Expert — every puzzle is generated with exactly one solution and graded by the hardest technique it actually requires, so the difficulty is honest. Play the daily puzzle to build a streak, use Notes, Hint, and Check when you are stuck, and race your own best time. There is no account and nothing to install; your times and streak are saved only on your own device. Read the how-to-play guide for the full rules and tips, or see how your data is handled in the privacy policy.