sudokly
Medium · Typical solve: 7 to 15 minutes

Medium Sudoku, Free Online

Balanced puzzles where pencil marks start to pay off.

EasyMediumHardExpertEvil
Medium00:00
About medium

What medium sudoku feels like.

Medium sudoku is the sweet spot. Most cells resolve with naked or hidden singles, but the last third needs pencil marks and a pair technique. A satisfying ten-minute game.

Typical solve time
7 to 15 minutes
Who it's for
Players comfortable with the basics who want a real workout.
Techniques
Naked and hidden singles, Naked pairs, Pencil marks

Medium sudoku FAQ

What is the difference between easy and medium sudoku?

Medium sudoku puzzles have fewer starting clues, typically 32 to 36, and reach a point where simple scanning stops finding moves. To finish you will usually need pencil marks and a basic pair technique.

When should I start using pencil marks?

Start using pencil marks as soon as you cannot find a single in a full scan. Mark every candidate digit in every empty cell, then look for naked pairs: two cells in the same group with the same two candidates.

How long does a medium sudoku take?

Most players finish medium sudoku in 7 to 15 minutes. If you regularly go over 20 minutes, you may be missing hidden singles. Try a slower scan before reaching for pencil marks.

Is medium sudoku always solvable with one unique solution?

Yes. Every Sudokly puzzle is verified to have exactly one solution.

Should I guess on medium sudoku?

No. Every medium sudoku can be solved with logic alone. Guessing means you have missed something. Back up and try a different technique.