- very easy
- easy
- medium
- tough
- very tough
- extreme

- very easy
- easy
- medium
- tough
- very tough
- extreme

Traditional Sudoku is a 9x9 puzzle grid made up of nine 3x3 regions. Each region, row, and column contains nine cells each.

The objective is to fill a 9x9 grid so that each column, each row, and each of the nine 3x3 boxes (also called blocks or regions) contains the digits from 1 to 9.

A cell is the smallest block in the game. A row , column and region consists of 9 cells and the whole game consists of 81 cells. A region has thicker lines surrounding it. This simply makes it easier to play the game.