Diagonal Sudoku online (Sudoku X)
Play Diagonal Sudoku — classic rules plus both long diagonals must contain 1–9.
About this Sudoku page
Also called Sudoku X. Highlighted diagonal cells mark the extra constraint while you solve.
FAQ
Everything you need to enjoy Sudoku with calm, focused play.
How do I play Sudoku online?+
Fill each row, column, and 3×3 box with digits 1 to 9 exactly once. Tap or click a cell, then choose a number from the keypad.
Is an account required to play Sudoku?+
No. You can start immediately in your browser without creating an account.