9×9 only
DIGIGMA Sudoku is 9×9. Nine rows, nine columns, nine 3×3 boxes, digits 1 through 9.
That is the classic form. It is what Play opens. The bands run from Beginner through Extreme on that one size.
Other sizes exist in the world. They are not on this site. You will not find a 6×6 or a 16×16 here.
If you want the rules, How to play Sudoku is the page. If you want a board, Play Sudoku.