Price per square foot is a very common measurement in the real estate industry. You might use it to assign a selling value to your house or to gauge what kind of deal you're getting when you rent office space. The same figure can also crop up in the construction industry when you're pricing out repairs or materials. Either way, calculating this value is as easy as remembering that when you see the word "per" in a word problem, it means there's a fraction involved.
Identify Your Price and the Square Footage
Write out your fraction with the total price of the real estate, repairs or materials you're considering in the numerator (top number), and the total square footage involved in the denominator (bottom number). So if you're considering a home that costs $250,000 and measures 2100 square feet, you'd have:
$250,000 / 2100 ft2
Remember that you can also write a fraction with a division symbol, and it doesn't change the value:
$250,000 ÷ 2100 ft2
Perform the Division
Perform the division indicated by your fraction. The result will be your price per square foot. To continue the example, you have:
$250,000 ÷ 2100 ft2 = $119.05/ft2
Notice how the units have been carried over into the right side of the equation. Always label each term of the calculation with the units used, otherwise, it's easy for you or anyone else who looks at your numbers to get confused and think you're looking at some other unit of measure, like price per square yards.
TL;DR (Too Long; Didn't Read)
If your measurements are in something other than square feet, you can either convert them to square feet before you do these calculations, or keep the same unit and label it throughout, in which case your answer will be in terms of that unit instead of square feet. For example, in the flooring industry it's common to calculate materials and prices in terms of square yards.
Calculating Total Price From Price Per Square Foot
You can also use your knowledge of price in dollars per square foot to figure out the total cost of a project. For example, perhaps a contractor has quoted you a price of $10 per square foot to refurbish an office that measures 1,000 square feet. To find the total price, multiply the total square footage by the price per square foot in dollars. The result is your total price for the repairs:
1000 ft2 × $10/ft2 = $10,000
Again, make sure that you label all the units involved, especially if you're dealing with flooring, where measurements in square yards are very common.