Sudoku for Beginners

Start with the three rules

Every row, column and 3×3 box must contain digits 1 through 9 once. You do not need arithmetic: the numbers act as symbols, and each placement is determined by what already appears around the cell.

A beginner solving routine

1. Choose an Easy puzzle.
2. Find a row, column or box with many given digits.
3. List the missing numbers mentally or with notes.
4. Check each empty cell against its row, column and box.
5. Place a number only when one position remains possible.

Learn two kinds of singles

A naked single is a cell with only one possible candidate. A hidden single occurs when a number can appear in only one cell within a row, column or box, even if that cell still appears to have several candidates. These two patterns can solve many Easy puzzles.

When should you use notes?

Use notes after obvious placements have been exhausted. Write only candidates that survive all three checks. Remove a candidate when the same number is placed in the connected row, column or box.

Why guessing causes problems

A guess may appear harmless, but one wrong value can make several later placements look valid. If you feel forced to guess, return to the grid and scan a different unit or a single digit across all nine boxes.

Accuracy matters more than speed. Once you can explain each placement on Easy, move to Medium difficulty.