How to Play Sudoku (Beginner Guide)
Sudoku is a logic-based number puzzle played on a 9×9 grid. The objective is simple: fill the grid so that every row, every column, and every 3×3 box contains the numbers 1 through 9 exactly once.
Despite the numbers, Sudoku is not about math. It’s about logical deduction, pattern recognition, and careful elimination.
Sudoku Rules Explained
- Each row must contain numbers 1–9 without repetition.
- Each column must contain numbers 1–9 without repetition.
- Each 3×3 subgrid must contain numbers 1–9 without repetition.
- Pre-filled numbers cannot be changed.
Every valid Sudoku puzzle has only one correct solution, and it can be reached through logic alone — no guessing required.
How to Start a Sudoku Puzzle
Beginners should start by scanning rows, columns, or boxes that already have many numbers filled in. Look for a missing number and determine where it can logically fit.
If a row is missing the number 5, check its columns and 3×3 box to see where 5 is already used. The only valid empty position left is your answer.
Basic Sudoku Strategies for Beginners
- Scanning: Look across rows and columns to identify missing numbers quickly.
- Cross-hatching: Use intersecting rows and columns to narrow down valid placements.
- Using Notes: Write small candidate numbers to track possible values in each cell.
- Elimination: Remove candidates as soon as they become impossible.
Common Beginner Mistakes
- Guessing too early instead of using logic.
- Ignoring obvious rows or columns with many numbers filled in.
- Forgetting to update notes after placing a number.
- Rushing and overlooking simple eliminations.
Practice Sudoku Online
The best way to improve is consistent practice. Start with easier puzzles and gradually increase the difficulty as your pattern recognition improves.
You can practice instantly on Gridcore Sudoku or try the Daily Sudoku challenge.
Not sure which level to choose? Read our Sudoku Difficulty Levels Explained guide to understand the differences between Easy, Medium, Hard, Expert, and Master puzzles.
Frequently Asked Questions
How do you play Sudoku?
Fill each row, column and 3×3 box with the numbers 1 through 9 without repeating any number. Use logical deduction to work out where each number belongs.
Do you need math to play Sudoku?
No. Sudoku is not a math puzzle. It relies on logic and pattern recognition rather than arithmetic — the digits are just symbols.
What is the best way to start a Sudoku puzzle?
Begin by scanning rows, columns or boxes that already contain many numbers. Identify what is missing and eliminate impossible placements step by step.