Full House

Full House is the most fundamental Sudoku solving technique. It applies when a house (row, column, or block) has exactly eight cells filled, leaving only one empty cell. The missing digit is the only possibility for that cell.

Technique

1. Look for any row, column, or 3x3 block that has exactly 8 cells already filled.
2. Count which digits from 1-9 are already present in that house.
3. The one missing digit is the solution for the empty cell.

Tips

• Always scan the puzzle for Full House opportunities first - they're the easiest wins.
• Full Houses often appear after you've placed several digits using other techniques.
• Check all three house types: rows, columns, and blocks.