Advanced Pattern Logic
Expect techniques like X-Wing, Swordfish, and chain-based eliminations in harder boards.
Free Online Play
Play Evil Sudoku Online
This site is built for players who want genuinely hard sudoku. Start a free evil sudoku puzzle now, switch between daily and random modes, and solve with notes, undo, and a clean board that works on desktop and mobile.
What Makes It Hard
What Is Evil Sudoku?
Evil sudoku is the hardest mainstream sudoku difficulty for many players. A good evil sudoku puzzle usually demands more than singles and easy candidate cleanup. You often need advanced logic, especially when the grid stalls and basic scanning stops working.
Daily and Random Modes
Use daily mode for a shared challenge or random mode for unlimited hard sudoku practice.
Built for Serious Solvers
Notes, undo, reset, and a distraction-free interface make it easier to work through long solves.
Player Paths
Choose the Right Evil Sudoku Page
Daily Evil Sudoku
Visit the daily landing page if you want one fresh evil sudoku puzzle each day and a consistent challenge to revisit.
17 Clue Sudoku
Explore minimum-clue puzzles and the hardest sudoku angle through the dedicated 17 clue challenge page.
How to Solve Evil Sudoku
Learn the solving roadmap for hard puzzles, from candidate tracking to advanced eliminations.