31% complete
25/81 correct ยท 25 filled
Under 20 Sudoku
Ultra-sparse boards with fewer than 20 starting clues.
Instant validation
Mark wrong placements as you enter them.
Reveal mistakes
Toggle visible mistake highlights when you want a cleanup pass.
Hints
0
Win rate
0%
Streak
0
Pick a cell to start.
Sudoku with fewer than 20 starting clues
This new level is built for players who want a much sparser board than the usual expert page. Every puzzle here starts with fewer than 20 clues, which means more pressure, more note work, and a slower solving rhythm.
What makes it different
Standard expert Sudoku is already sparse. This section goes further by generating boards with under 20 givens, so the early game stays much more open.
Best way to approach it
Use notes mode early, rescan the most constrained units often, and avoid emotional guessing. These boards reward patience more than speed.
Keep exploring
If you want a different kind of pressure, try Killer Sudoku. If you want to step back into the standard ladder, head to expert Sudoku.