A Sudoku that teaches you to think, not just to fill in numbers.
Every puzzle here is solvable by logic, and every hint teaches the actual technique — naked singles, hidden pairs, X-Wing, swordfish — instead of just revealing the answer. Solve calmly, at your own pace, with a board that stays quiet and focused so your mind can do the same.
Play entirely offline. No account, no sign-in, no data collection, no third-party ads — ever. Sudoku, uninterrupted.
FOR EVERY SKILL LEVEL
• Learn on 4×4, build confidence on 6×6, and master the full 9×9 grid
• Five difficulty tiers, Breeze through Zenith, so growth always feels earned
• Notes and undo let you explore ideas without fear of a wrong move
HINTS THAT TEACH
• Stuck cells come with hints that name and explain the logic — naked singles, hidden singles, pointing pairs, X-Wing, swordfish, and more
• Learn the technique once, and start spotting it yourself
A DAILY CHALLENGE WORTH KEEPING
• One puzzle a day, the same for every player worldwide
• Works completely offline — no connection, no account, no missed streaks because of bad signal
TRACK YOUR OWN PROGRESS
• Per-size statistics and streaks, because a 9×9 best time and a 4×4 best time aren't the same accomplishment
• Compare yourself to your own history, not a leaderboard
DESIGNED TO BE LOOKED AT, NOT JUST USED
• Luminous — a premium dark theme with soft, focused light
• Paper & Ink — a warm, analog light theme that feels like fine stationery
• A short cinematic intro that sets the tone without getting in your way
RESPECTS YOUR TIME AND YOUR DEVICE
• About 5MB — light enough to install without a second thought
• No noisy achievements, no energy timers, no pressure tactics — just Sudoku, done well
No ad networks. No account. No data leaves your device.
Calm Sudoku that teaches real technique. 4×4 to 9×9, offline, no ads.