What is Extreme Sudoku on Pure Sudoku?
Extreme describes the toughest solving experience; Pure Sudoku’s hardest current web difficulty is named Expert.
Pure Sudoku
Hardest web puzzles
Extreme Sudoku rewards patient candidate work.
Pure Sudoku’s hardest current web tier is Expert. If you call the toughest puzzles extreme, master, or evil Sudoku, this is the right place to prepare and start.
- Current tier
- Expert
- Core tool
- Candidate notes
- Rule
- Logic, not guessing
What makes a Sudoku feel extreme?
Fewer immediate placements force you to preserve accurate candidates and combine several deductions.
- Finish full scans before assuming the board is stuck.
- Look for locked candidates, pairs, triples, and fish patterns.
- Treat every elimination as progress; a placement may come several moves later.
A reliable hard-board routine
Use the same deliberate scan order each time.
- Mark candidates cleanly across the unresolved cells.
- Check rows, columns, and boxes for restricted candidate sets.
- After every elimination, scan again for newly created singles.
Continue playing
Choose your next Sudoku route.
FAQ
Quick answers before you play.
Can extreme Sudoku be solved without guessing?
Yes. A valid standard Sudoku has a logical solution, although advanced candidate patterns may be required.
Where should I practice first?
Start on Hard if candidate notes are new, then move to Expert when pairs and line interactions feel comfortable.
Ready to solve?
Start the hardest puzzle
Open a clean Pure Sudoku board in your browser and put the guide into practice.