A square foot is a unit of area that is defined as the area of a square with each side measuring one foot in length. Since one foot is equal to 12 inches, to find out how many inches are in a square foot, you need to square the number of inches in a foot.
To calculate this, you take:
12 inches (length) × 12 inches (width) = 144 square inches.
Therefore, there are 144 square inches in a square foot.