Select a cell, then tap a number to fill it in.
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Medium puzzles reward a more systematic view. Singles may still appear, but candidate notes and small relationships between cells become the dependable way forward.
Medium Sudoku · from seeing to analysing
Use candidates to uncover the next opening
Medium puzzles reward a more systematic view. Singles may still appear, but candidate notes and small relationships between cells become the dependable way forward.
A useful routine for medium puzzles
- 1Scan for singles first; each placement can reveal another simple move.
- 2Add candidates to the areas where scanning no longer gives a certain digit.
- 3Compare candidate pairs within one row, column or box before looking for larger patterns.
Best for
You solve easy puzzles without guessing.
You will practise
Complete candidate notes and Naked Pairs.
Move on when
You keep candidates clean and can spot a clear pair.
Why Sudoku Luna?
- Four difficulty levels from easy to expert
- Daily challenge with a global leaderboard
- Smart hints that teach real solving techniques
- Notes, undo/redo and automatic error checking
- Dark and light mode with an elegant design
- Print puzzles as PDF in multiple layouts
Frequently asked questions
Why do medium puzzles feel different from easy ones?
They more often require you to keep and compare candidates instead of filling only immediately obvious cells.
Do I need to guess in medium Sudoku?
No. A valid Sudoku Luna puzzle has a logical next step; notes and the hint explain how to find it.
Which candidate notes matter at medium level?
Record the remaining options completely where simple singles run out. Only consistent notes reveal pairs and eliminations.
How do I spot a Naked Pair?
Two cells in the same row, column or box contain exactly the same two candidates. Those digits can then be removed from the other cells in that unit.
Explore Naked PairWhat helps when progress stops?
Check every new elimination and single again first. If the grid remains still, use a hint as an explained next step instead of trying digits.