Lesson 7 · Solve safely
Common Sudoku Mistakes
Recognise guessing, missed conflicts, and unreliable notes before they derail a puzzle.
See the logic move
Use Next to reveal each reason. On the final step, tap the highlighted cell to complete the move yourself.
Step 1 of 3
A tempting guess
This cell still has candidates 5 and 7. Neither is proven.
What the board is showing
FocusStart here. This is the cell or area being investigated.R5C5
Explain it simply
Mistakes usually happen when we rush. A short three-way check keeps the board trustworthy.
Step by step
- Avoid guessing between two candidates.
- Recheck row, column, and box.
- Keep candidate notes current.
- Pause after each placement.
Quick check: What is the safest action when two candidates remain and neither is proven?
Leave both notes and continue solving elsewhere.
Turn logic into skill