How to play
The rules
A sudoku is a 9 × 9 grid divided into nine 3 × 3 boxes. Some cells already contain a number: these are the givens, and they can't be changed.
Fill every empty cell with a number from 1 to 9 so that:
- every row contains each number from 1 to 9 exactly once;
- every column contains each number from 1 to 9 exactly once;
- every 3 × 3 box contains each number from 1 to 9 exactly once.
Every Sudokumania puzzle has exactly one solution and can be solved by logic alone: you never need to guess.
How to use Sudokumania
Placing a number
Tap a cell, then tap the number on the pad. To remove it, tap the same number again or use Erase. Under each number on the pad you can see how many are left to place.
Locking a number
To place the same number in several cells, press and hold that number on the pad until it changes color: now every cell you tap gets that number. Tap it again to unlock it.
Notes
Turn on Notes to pencil in the possible numbers for a cell. You can also press and hold an empty cell: a small pad opens just for that cell's notes. When you place a number, Sudokumania removes it from the notes in the same row, column and box (you can turn this off in Settings).
Mistakes and conflicts
If you put two equal numbers in the same row, column or box, the cell turns red. Sudokumania doesn't tell you whether a number matches the solution: it only flags broken rules. The rest is the fun of the game.
Undo and pause
Undo steps back one move at a time. Pause stops the clock and hides the grid. If you close the app mid-game, you'll find it exactly as you left it.
Keyboard shortcuts
| Key | What it does |
|---|---|
| 1–9 | Places the number in the selected cell |
| Shift + 1–9 | Adds or removes a note |
| 0, Backspace, Delete | Clears the cell |
| Arrow keys | Move the selection |
| N | Turns notes on or off |
| Ctrl/⌘ + Z | Undo |
| P | Pause and resume |
Four techniques to get started
1. Only one place
Pick a number, say 7, and a box where it's missing. Look at the rows and columns that cross the box: if they already contain a 7, those cells are ruled out. If only one free cell is left, the 7 goes there. This technique solves almost every easy sudoku.
2. Only one number
Look at an empty cell and check which numbers already appear in its row, column and box. If only one number is missing, that's the answer.
3. The pointing box
If, inside a box, a number can only go in cells of the same row, that number can't go anywhere else in that row outside the box. Remove it from those notes: it often unlocks an "only one place" elsewhere. The same works for columns.
4. Pairs
If two cells in a row can only hold the same two numbers, say 4 and 8, those two numbers must go there. You can remove them from the notes of every other cell in the row. The same works for columns and boxes.
Easy sudoku need techniques 1 and 2, medium ones also need 3, and hard ones also need 4 and sometimes more advanced techniques.
The daily sudoku and your streak
Every day there are three new sudoku, the same for everyone: easy, medium and hard. They change at midnight, according to your phone's clock.
Solve at least one daily sudoku on consecutive days and your streak grows. When you finish, you see how many of that day's players were slower than you. There are no leaderboards with names: only your time counts.
You can play offline too: games are saved on your phone and sync as soon as you're back online.