How to Play
Fill the 9x9 grid so that every row, every column, and every 3x3 box contains the digits 1 through 9 exactly once. Tap a cell to select it, then tap a number on the pad (or use your keyboard). Every puzzle here has exactly one solution, reachable by pure logic — no guessing ever required.
- Daily puzzle: One shared puzzle per difficulty per day — the same grid for every player, so you can compare times. The Daily Puzzle button brings you back to it.
- New Puzzle: Pulls a fresh grid from a bank of 300 puzzles (100 each of Easy, Medium, and Hard), each pre-verified to have a unique solution.
- Notes: Toggle Notes (or press N) to pencil in candidates. Correct placements automatically clean up notes in the affected row, column, and box.
- Error checking: Wrong digits turn red immediately and count toward your mistakes tally.
- Keyboard play: Arrow keys move the selection, 1–9 place digits, Backspace erases.
Which difficulty should I pick?
Easy (about 40 given digits) solves with basic scanning — ideal if you're new or warming up; our Sudoku tips guide covers everything you need. Medium (about 32 givens) rewards pencil marks and pairs. Hard (about 26 givens) expects systematic candidate work — if you stall, the solving techniques library explains 30+ techniques from naked singles to X-wings. Complete rules for beginners live in our How to Play Sudoku guide.
Frequently Asked Questions
Is this Sudoku game really free?
Yes. Every puzzle on this page is free to play in your browser with no signup, no install, and no paywall — there's a new daily puzzle for each difficulty, plus hundreds more behind the New Puzzle button.
How does the daily puzzle work?
The game deterministically selects one easy, one medium, and one hard puzzle from the bank each day, so every player worldwide gets the same daily grid. Come back after midnight for the next one.
Does the game tell me when I make a mistake?
Yes — wrong digits are highlighted red immediately and tallied, so the grid never silently goes off the rails. Erase and correct any cell you filled at any time.
Can I play on my phone?
Absolutely. The board and number pad are designed mobile-first. And if you enjoy this, the free Sudoku - Brain Puzzles iOS app adds 11 more variants — Killer, Sandwich, Jigsaw, Kropki, Mega 16x16, and more — plus smart hints that teach, daily streaks, and iCloud sync.