## Welcome to sudoku-game.org!

We offer 3 sudoku types — classic sudoku, sudoku-diagonals and sudoku with extra zones. Each sudoku type can be played with numbers and letters.

**5 difficulty levels:**

- «Very Easy» — 40 cells are opened and sudoku has the one solution;
- «Easy» — 30 cells are opened and sudoku has the one solution;
- «Normal» — 25 cells are opened and sudoku has the one solution;
- «Hard» — 22 cells are opened and sudoku has the one solution;
- «Very Hard» — 20 cells are opened and sudoku can have more than one solution.

* Different sudoku types can have different number of initially opened cells.

**You can play:**

- with mouse — click a cell and choose number;
- with keyboard — using keyboard arrows ← ↑ → ↓ navigate to a cell and type number;
- with mouse and keyboard — hover a cell with mouse and type number with keyboard.

**Print**

You can also print 6 sudoku grids on a paper sheet here choosing difficulty level and sudoku type for each grid.

## Sudoku Rules

Sudoku is a grid of size 9x9 divided into 9 smaller squares, each having 9 cells. To solve sudoku you need to fill the grid with numbers from 1 to 9 so that numbers of each row, each column and each of the 9 smaller squares were different.

An example of solved sudoku:

## Other sudoku-like games

In addition to the main sudoku game there are a number of variations in which additional conditions are defined:

- Irregular sudoku — similar to the main sudoku except that 9 smaller squares in the grid can be of different shapes;
- Sudoku of different sizes — similar to the main sudoku except that it can be bigger or smaller in size (4x4, 16x16, 25x25 etc.);
- Sudoku with additional regions — in this type of sudoku additional areas are set where in addition to rows, columns and 3x3 squares numbers also cannot repeat;
- Sudoku «Sums» — the grid is divided into blocks for which the sum of all contained numbers in it is specified;
- Sudoku «Even-odd» — some cells are marked with circles (or with a different color) which can be either even or odd only;
- Sudoku «More-or-less» — for this type of sudoku the sign in some of the neighboring cells is specified indicating the greater number in these cells;
- Sudoku «Dots» — the black or white dot is specified between some neighboring cells indicating that numbers differ by 1 or twice;
- Sudoku «Septums» — some cells are separated with septums in which numbers differ by 1.