Sudoku Smart: Classic & 16x16

Play sudoku offline, free, with no sign-up and no interruptions to your first games.

Sudoku Smart is a classic number puzzle and brain game built for people who actually solve. Every puzzle is generated on your device with a guaranteed single solution, so there is no guessing and nothing to download. Play offline on a plane, on the metro, or anywhere with no wifi.

🔢 FOUR BOARD SIZES, INCLUDING 16x16
Start on a 4x4 mini grid, settle into the classic 9x9, or take on a full 16x16 sudoku — a size most puzzle apps never offer. Each size scales properly to your screen, including tablets and Chromebooks.

📈 EASY TO EXPERT
Four difficulty levels, from Easy for learning the ropes to Expert for seasoned solvers. Expert builds each puzzle with rotational symmetry, the way handcrafted sudoku is composed.

🔥 A DAILY CHALLENGE WORTH KEEPING
A new daily puzzle every day, with a streak that grows as you keep it. Track your history on a calendar, see your best run, and get a reminder before a streak is about to break.

💡 LEARN THE LOGIC, NOT JUST THE RULES
New to sudoku? A short guided tutorial walks you through your first puzzle. Ready for more? How to Play covers the real solving techniques — scanning, naked singles, hidden singles, pencil marks and pointing pairs — each with a diagram. Hints are logically derived, so they show you why a number belongs there, not just what it is.

✏️ TOOLS THAT STAY OUT OF THE WAY
- Pencil marks, with the option to clear them automatically as you place numbers
- Remaining counts, so you can see how many of each number are left
- Duplicate warnings you can switch off for a purer challenge
- Unlimited undo and redo
- Auto-save: close the app mid-puzzle and pick up exactly where you left off

🏆 YOUR PROGRESS, KEPT
Daily brain training you can measure: best times and scores for every grid size and difficulty, win rate, perfect games, streaks and ten achievements to unlock. Your statistics and saved game are backed up, so a new phone does not mean starting over.

🌙 MADE TO LOOK AT FOR AN HOUR
Five themes including Midnight and Gold Luxury, full dark mode, the Outfit typeface, and animations you can turn off entirely. The board is fully labelled for TalkBack, so it can be played with a screen reader.

⭐ FREE, WITH A FAIR UPGRADE
The full game is free. Sudoku Smart PRO is a single one-time payment — no subscription — that removes every ad forever, unlocks the premium themes and gives you unlimited hints. New players get their first sessions with no full-screen ads at all.

No account. No login. No puzzle packs to buy. Just sudoku, free and offline.

Download Sudoku Smart and start today's puzzle.