Android & iOS appsComing soon
Sudoku Variants
Play on the go with daily boards, coaching hints, offline solve, and synced progress.
✓ Offline solving✓ Daily streak sync✓ Smart hints
Launching soon on Android and iOS
Daily Sudoku Guide
About Diagonal
More
Daily Sudoku Guide
About Diagonal
Daily Sudoku Guide
Diagonal Daily Sudoku for 2026-09-13
Play today's Extreme Diagonal Daily Sudoku online for 2026-09-13 on Puzzella. Diagonal Daily Sudoku adds an extra constraint to the standard grid, making it a stronger fit for players who already enjoy classic Sudoku and want a more tactical daily challenge.
How Diagonal Daily Sudoku works
- Standard Sudoku rules still apply across every row, column, and 3x3 box.
- The main diagonal must contain 1 to 9 without repeats.
- The anti-diagonal must also contain 1 to 9 without repeats.
Variant notes
Why Diagonal Sudoku feels different
- Diagonal Sudoku increases cross-board interactions, so every placement affects more of the grid.
- It works well for players who already solve classic Sudoku comfortably and want an extra layer of logic.
- The diagonal constraint makes candidate tracking and cross-checking more important than in standard Sudoku.