The objective is to fill a 9x9 grid with digits so that each column, each row, and each of the nine 3x3 subgrids that compose the grid contain all of the digits from 1 to 9.
Select a difficulty and press "New Game" to begin.
Drag a number from the palette below and drop it onto an empty cell on the board.
If the number is correct, it will fill the cell. If it's incorrect, you'll get a mistake. Be careful, you only get 3 mistakes!