Medium Sudoku — play free
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Pause
Settings
Keyboard: arrows — select a cell, 1–9 — digit, N — notes, Delete — erase, Ctrl+Z — undo.
Medium sudoku
Medium puzzles start with 28–32 digits. You still don't need advanced techniques, but obvious moves are rarer: more often you have to find a "hidden single" — a digit that has only one possible place in a row, column or box, even though that cell seems to allow several digits.
This is the most popular level: a puzzle takes 10–20 minutes and trains attention nicely. Use pencil marks so you don't have to keep the candidates in your head.