One move, explained
Stuck on a Sudoku?
Find your next step.
Choose a digit on this practice board. See why it fits, then use the same reasoning in your puzzle.
Your turn
What goes in the outlined cell?
Check its highlighted row, column and 3×3 box, then choose a digit.
A complete practice board. The other blanks stay available for later moves.
Choose a digit
Take your time. One digit fits all three checks.
Keyboard: Tab to the practice, then use 1–9. Arrow keys move between digit buttons.
See why only one digit fits
A digit cannot repeat in a row, a column or a 3×3 box. For row 5, column 5, check all three:
- Row 5Already contains 1, 3, 4, 8.
- Column 5Already contains 1, 2, 6, 7, 8, 9.
- The central boxAlready contains 2, 3, 6, 8.
Only 5 remains. Place 5 in row 5, column 5. This is a Single Candidate (Naked Single): the cell has one possible digit.
You found a step. Keep learning.
Learn the next move, too.
Practice with guided hints and step-by-step techniques in Sudoku Coach.
For iPhone and iPad · Opens the App Store
Take it back to your puzzle
Start with one cell.
Check its row, column and box. Rule out the digits already there. When just one candidate remains, you have a move you can explain.
If your board needs a different technique, use the stuck-puzzle checklist to choose what to look for next.