Classic Sudoku

Medium Sudoku

Play free Medium Sudoku online. Every Medium puzzle here needs hidden singles, and sometimes locked candidates, as well as naked singles: logic only, never guessing.

40,000+ puzzles24 to 32 cluesOne solution each
5
6
8
4
1
3
6
3
9
5
8
1
7
6
3
8
9
1
2
5
9
3
2
5
3
4
9
2
A Medium puzzle from our collection, 28 clues

What makes a Sudoku Medium here

Every puzzle on Sudoku Challenge is solved by our grader step by step, the way a careful person would: at each step it uses the simplest technique that works. A puzzle's level is the hardest group of techniques it cannot be finished without.

Easynaked singles only: every step is a cell with one possible digit.
Mediumadds hidden singles (a digit with one possible cell in a row, column or box) and locked candidates.
Hardadds pairs, triples and quads, naked and hidden, the unique rectangle and BUG+1.
Extremeneeds at least one advanced pattern, such as the X-Wing, XY-Wing, Skyscraper or Swordfish.
Diabolicalneeds the longest chains and largest patterns our solver knows, such as the XY-Chain, Jellyfish or ALS-XZ.

So a Medium puzzle is one that naked singles cannot finish on their own, yet never needs a pair, a triple or anything harder. Its score sits between 1,000 and 1,999 points, shown before you start.

Our Medium puzzles have 24 to 32 clues, 28 on average. What counts is the techniques.

The techniques you need

First the ones every level uses: Naked Single. Then the Medium techniques, with how often our grader used each one across our 40,000+ Medium puzzles:

TechniqueMedium puzzles using it
Naked SingleEasy levelevery one
Hidden Singleevery one
Locked Candidates7%

Counted October 2026 over every puzzle on the site. More in Sudoku by the Numbers.

How to solve a Medium Sudoku

  1. Start with naked singles: cells with only one possible digit.
  2. When none is left, turn it round: pick a digit and a row, column or box, and look for the one cell where that digit can go. That is a hidden single.
  3. Scan each digit from 1 to 9 across the boxes: a digit already placed in two boxes of a band often has one cell left in the third.
  4. If a digit’s candidates in a box all sit in one row or column, eliminate it from the rest of that row or column: locked candidates.
  5. Every new digit opens more singles, so go round again.

Medium puzzles across the site

Play MediumAn unlimited supply in Classic, with candidates, Next Step hints and undo.The daily practiceA Medium puzzle every day, the same for everyone, to replay with every tool.TournamentsRace other players on the same Medium puzzles for 15 minutes to an hour.DuelsOne opponent, the same Medium puzzle, the same clock.Printable Medium SudokuPacks of 12 to print, with the answers on the last page.Learn the techniquesEvery technique above, step by step, with real examples.
The other levels:Easy SudokuHard SudokuExtreme SudokuDiabolical Sudoku

Questions about Medium Sudoku

What makes a Sudoku medium?

A Medium puzzle needs hidden singles: at some point no cell has only one possible digit, but a digit has only one possible cell in a row, column or box. Some also need locked candidates. None needs a pair or anything harder.

What is the difference between Easy and Medium Sudoku?

Easy needs only naked singles. Medium adds hidden singles, which every Medium puzzle here uses, and locked candidates, which about 7% use.

How many clues does a medium Sudoku have?

Our Medium puzzles have between 24 and 32 clues, 28 on average.

Is there a daily Medium Sudoku?

Yes. The daily practice has a Medium puzzle every day, the same for everyone, that you can replay with every tool. Tournaments and duels can be played at Medium too.