What is the formula to calculate square footage?

The formula to calculate square footage is indeed based on multiplying measurements of length and width in feet. When you multiply feet by feet, you get the area in square feet. This is because square footage is a measurement of area, which requires two dimensions—length and width—both expressed in the same unit (feet, in this case).

When considering the other options, multiplying inches by inches will yield square inches, which is not useful for calculating square footage, which is traditionally expressed in square feet. Similarly, multiplying feet by inches mixes units improperly and does not provide a correct measurement of area. Lastly, the multiplication of feet by feet by feet would calculate cubic footage, which measures volume, not area. Hence, the formula that accurately calculates square footage by using two dimensions expressed in the same unit is feet multiplied by feet.