Sudoku Guide: How to Play, Tips & Strategy

🎮 How to Play

Sudoku asks you to fill a 9x9 grid so every row, every column and every 3x3 box contains the digits 1-9 exactly once. No arithmetic is involved — it is pure constraint logic, and a well-formed puzzle always has one unique solution.

🎯 Tips & Strategy

Scan for 'naked singles': a cell where eight of the nine digits are already blocked by its row, column and box leaves only one option.
Use 'hidden singles': within a row, column or box, if a digit can only legally go in one cell, place it there.
Pencil in candidates for tricky cells, then eliminate them as you place confirmed digits.
Look for 'pointing pairs' — when a digit in a box is confined to one row or column, you can remove it from the rest of that line.
Work the most constrained regions first; boxes or lines that are nearly full give the fastest confirmed placements.

❓ Frequently Asked Questions

Where should I start a Sudoku?

Start where the grid is most filled — the rows, columns or boxes with the fewest empty cells reveal forced placements first.

Do you ever need to guess in Sudoku?

Properly made puzzles are solvable by logic alone. If you feel stuck, you are missing a technique like hidden singles or pointing pairs, not lacking a guess.

What makes a Sudoku 'hard'?

Harder puzzles need more advanced chains of deduction and offer fewer obvious singles, so you must combine several techniques to progress.

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