Play 4 brain teasing logic games - Sudoku | Killer Sudoku | MathDoku | X-Sudoku - with thousands of puzzles. Don't get stuck - 9 digits' helpers guide your next move and teach you solution strategies. β’ choose levels from beginner to master β’ easily enter digits and pencil marks β’ get step-by-step hints for your next move β’ unique solutions, no guessing needed β’ plenty of settings to tweak your game experience β’ no ads 9 digits was created by Ivonne & Marcus who love to play logic games.