A new extreme Sudoku puzzle every day. With only 17-21 clues near the mathematical minimum, the hardest daily challenge available.
Extreme daily puzzles require mastery of the complete strategy toolkit: forcing chains, multi-coloring, Jellyfish, XY-Wing, and unique rectangles. Basic, intermediate, and standard advanced techniques will only solve a small fraction of the grid.
With only 17-21 clues provided, the grid starts nearly empty. Perfect pencil marking is essential - every candidate must be tracked with absolute precision. A single error in your candidate lists can make the puzzle appear unsolvable.
Exhaust every technique in order of complexity: singles, pairs, triples, pointing, box/line reduction, X-Wing, Swordfish, XY-Wing. When all of these stall, turn to forcing chains. Pick a bivalue cell and trace the implications of each candidate through the grid. If one leads to a contradiction, the other must be true.
Multi-coloring extends basic coloring by tracking multiple candidate networks simultaneously. Jellyfish patterns involve four rows and four columns, providing powerful eliminations. Read our extreme solving guide for comprehensive technique walkthroughs.
A daily extreme puzzle is the ultimate test of solving ability. Do not be discouraged if you cannot finish every puzzle - the practice of searching for complex patterns builds skills that transfer to every level. Many championship solvers credit daily extreme practice as the key to their improvement.
Consider warming up with a daily easy or medium puzzle before tackling the extreme challenge. This builds momentum and ensures your basic technique execution is sharp. Read more about building a Sudoku daily routine and how to get faster at Sudoku.
Each daily extreme Sudoku puzzle contains between 17 and 21 given clues. This places extreme puzzles near the mathematical minimum of 17 clues needed for a unique solution, making them the most challenging daily puzzles available.
Most experienced solvers spend 60 to 120 minutes or more on an extreme puzzle. Some particularly difficult extreme puzzles may require multiple sessions. The sparse grid means very long chains of deduction before any number can be placed with certainty.
Extreme puzzles demand the full toolkit: forcing chains, multi-coloring, XY-Wing, jellyfish, unique rectangles, and sometimes even more exotic techniques. You must be fluent in every strategy from beginner through expert level before attempting extreme puzzles.
Expert puzzles typically have 22-28 clues and can often be solved with XY-Wings, coloring, and forcing chains. Extreme puzzles have only 17-21 clues, frequently requiring longer and more complex forcing chains, multi-coloring networks, and jellyfish patterns that are rarely needed at expert level.
Yes. A new daily extreme Sudoku puzzle is published every day at midnight. The puzzle rotates through our library of 100 extreme puzzles, providing the ultimate daily challenge for the most dedicated solvers.
Ready to put your skills to the test?
Try Final Sudoku - an ad-free Sudoku experience with smart tools