Full House
Overview
When a row, column, or box has only one empty cell, the missing digit goes there.
How It Works
Count the digits 1-9 in a house. If eight are present, the ninth must go in the sole empty cell.
When To Use It
Look for rows, columns, or boxes with only one empty cell.
How To Detect It
Scan each house. Count filled cells. If 8 of 9 are filled, place the missing digit.
Visual Example
Step 1 of 11
The Sudoku Grid
A sudoku grid is 9 rows, 9 columns, and 9 boxes of 3×3 cells. Your goal is to fill every cell so that every row, column, and box contains each digit 1 through 9 exactly once.
Practice
Your goal: fill the 3 highlighted cells. Select a cell, then pick a number.
Three cells are each the last empty cell of their row, column and box. Find them and place the missing digits.
Use it in a real game
Easy puzzles need nothing beyond the Easy techniques.
Play an Easy puzzle