Your play guide
How to Play Sudoku: A Clear Path to Solve
Choose your variant and learn in a useful order: understand first, apply next, then practise with purpose – always without guessing.
Classic Sudoku
Classic Sudoku: logical, calm and step by step
Classic Sudoku is built only on what can be proven from a row, column and 3×3 box. Start with certain placements, then widen your view to candidates and patterns.
Mini grid: find the certain cell
Tap the highlighted cell first. Which digit completes the row from 1 to 9?
Mini grid: find the certain cell
0/3 solved
Quick check
When may you place a digit with confidence?
The three rules that always apply
- Every row contains the digits 1 to 9 exactly once.
- Every column contains the digits 1 to 9 exactly once.
- Every 3×3 box contains the digits 1 to 9 exactly once.
Your confident solving routine
- 01Scan rows, columns and boxes with only a few empty cells first.
- 02Check an empty cell against its row, column and box: if only one digit remains, place it.
- 03When several digits remain possible, add candidate notes and then look for a single remaining candidate.
Three common beginner mistakes
- Do not guess: a digit belongs in a cell only when logic proves it.
- Do not look at a box in isolation: every cell is constrained by a row, column and box.
- Do not treat notes as an answer: they are possibilities that shrink when new information appears.
When the easy moves run out
Use a hint for the next genuine logical step or train the matching technique in the learning path. That keeps every solve understandable.
Why Sudoku Luna?
Frequently asked questions
Is Sudoku Luna really free?
Yes. All puzzles, the daily challenge, statistics and the print function are completely free to use.
Do I need an account to play?
No. You can play instantly. An account is only needed if you want to appear on the global leaderboard and sync statistics across devices.
How is the score calculated?
The score is based on difficulty, solving time, mistakes and hints used. Daily challenge streaks add a bonus of up to 50%.
Can I print puzzles?
Yes. The print page generates fresh puzzles as a PDF with 1, 2, 4 or 6 grids per page, optionally with solutions.