Sudoku for beginners, step by step

Understand the game before rushing

Numbers 1 to 9 appear once in every row, column and 3×3 region. Solving means crossing those three constraints, not calculating.

The aim of this guide is to turn that central rule into repeatable decisions. A good result comes from recognising the state of the game, choosing a plan and checking the consequence before acting.

Step-by-step strategy

Apply one idea at a time. Trying to change speed, route and decision rules simultaneously makes it difficult to understand why a game improved or failed.

Example: find a single candidate

If a cell could contain 2, 5 or 7, inspect its column and box. When the column already contains 2 and the box contains 5, the only possible value is 7.

1. List the numbers missing from the row.
2. Remove values already present in the column.
3. Check the 3×3 box and place the remaining candidate.

Common mistakes and how to correct them

• Choosing between two candidates without proof.
• Checking the row but forgetting the 3×3 region.

When one of these situations appears, pause before repeating the same input. Identify the earlier decision that created the problem; the useful correction normally happens one or two moves before the visible failure.

A short practice plan

Solve easy without mistakes and explain every exclusion, then raise difficulty while keeping the method.

Use three to five games for the same objective and compare the pattern, not only the best isolated score. Consistency is the clearest sign that the strategy is becoming a habit.

How scoring works

Higher difficulty gives a larger base; time and mistakes subtract points.

Leaderboards are useful for comparing results, but first compare against your own personal best and the quality of your decisions.

Frequently asked questions