Sudoku like on paper, smart like an app.
Three ways to play. Hints that actually teach you. Your stats stay with you. No ads, no fees, now and always.
What is Sudoku
The world's most popular logic puzzle. Five minutes to learn, an hour you can't put down.
No math required
Sudoku isn't about numbers, it's about patterns. Even though you fill the board with digits 1–9, you never add or multiply them. The digits are just convenient symbols. You could use letters A–I and nothing would change.
One rule
Every row, every column and every 3×3 box must contain each digit exactly once. Your job: deduce from what is already there, where the rest must go. No guessing, every puzzle has one unique solution.
Brain workout
A few minutes a day is real training for focus, working memory and logical thinking. You start for fun, you stay because it gets easier to concentrate on everyday tasks too.
Three ways to play
Pick a style for your mood. Switch on the fly - no reset, no penalty.
Assisted
Peer and same-digit highlights, error checking, undo/redo, hints. Comfortable learning, like a modern app.
Classic mode
Disables every helper. Just the board, you and logic - the way newspaper sudoku is solved. Place digits with confidence or not at all.
Zen
No timer, no mistakes counter, no score pressure. The board quiets everything but you and the numbers.
Every move has logic
Under the aesthetics sits a real engine. Every puzzle is solvable by pure logic - you never have to guess.
Naked Single, only candidate
A cell where only one digit can go, because every other digit is blocked by its peers (row, column and box). Simplest technique, often unlocks chains of further moves.
Explore all techniquesBy the numbers
No marketing fluff. Just what you actually get inside.
Three tips to get going
Small things that nudge you forward when you're stuck.
Start with "almost full" lines
Look for rows, columns or 3×3 boxes missing only 1–3 digits. Those are the quickest to fill, an easy win that often unlocks the rest.
Chase one digit
Pick one digit (say 5) and check where it already is. Often you'll find that in a nearby box it can only go in one spot, because other rows and columns are blocked.
Use notes
When you are unsure, put 2–3 candidates as notes in the cell. Coming back later you will see that other moves have eliminated some, and you know which one stays.
Puzzle of the day
Every day a fresh puzzle, same one for everyone playing worldwide. See how you do today.
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