If you’re selling your home in the near future, one thing that you will want to find out is its exact size. Calculating the square footage will be a critical detail that buyers will want to know and will need to be included in your listing. Your home’s square footage is a critical element in establishing the listing price of your home.

But if you don’t come up with an accurate measurement, the value of your home could suffer.

If your home was a completely square box, calculating its square footage would be easy. But such is typically not the case, as most homes come with a host of little intricacies that can make measuring its square footage complicated. Couple that with the fact that different people measure square footage differently, and you can see how this particular calculation can be confusing.

That said, the standards for measuring square footage are determined by the American National Standards Institute (ANSI). But it is not mandatory to comply with the ANSI standard, though it’s highly recommended.

The question is, how do you calculate the square footage of your home to find out how big it is?

**Calculating the Square Footage of Your Home**

To make things easy for you, start off by sketching a floor plan of the interior of your home. Ideally, each level should be sketched out separately, and be sure to leave out any unfinished areas.

Break down each floor of your house into easily-measured rectangles, which will help eliminate the temptation to guess the length and size of rooms with walls that are not perfect.

Measure the length and width of each rectangle. While a measuring tape can work to calculate the square footage of your home, a laser measuring tool would be much more convenient. Once you have the length and width accurately measured in feet, you can calculate the area of each rectangle by multiplying the length by the width to figure out the area.

Jot these numbers down in the appropriate spaces on the sketch you drew, then add them up to get the total square footage of your home. You likely might wind up with fractions, so just round up to the nearest foot.

If some of the rooms in your home have subsections, break the room down into smaller parts and measure each box on its own. Once you have all the measurements, add each of them up to obtain the total area of the room. For instance, in the case of a 700 square-foot bedroom with a 150 square-foot closet, both of these spaces would be measured separately. The total would then be 850 square feet when added together.

**What About Rooms That Are Irregular in Shape?**

Calculating the area of a square or rectangular room is easy enough. Simply multiply the length by the width and you’ve got your answer. But calculating the area of a room that’s circular or irregular in shape will require that you use the appropriate mathematical equations to come up with the final area. There several different mathematical equations that can be used to determine the area of a variety of shapes, so you’ll need to establish the shape of the room before using the appropriate equation.

There are also online calculators that you can use. Just plug in the shape and necessary measurements, and the calculator will do the hard work for you.

**Not All Areas of the Home Should Be Included in Your Calculation**

When calculating the square footage of your home, it’s important to note that not all areas should be included in the final number. For starters, any space that is below grade should not be part of the total square footage, which means any basements or crawl spaces would be excluded.

Attics would typically be excluded as well, unless the space is finished and there is at least a seven-foot clearance to make the space potentially habitable. If that’s the case, the attic would be included in your calculation. Garages, sheds, patios, and exterior staircases are also not to be included in your square footage calculation.

That said, you might still want to know how large these particular spaces are for your own knowledge. You can even include these dimensions in the listing for buyer information, as long as it is clear that they are not part of the overall square footage of the home.

**The Bottom Line**

If your home has perfectly square or rectangular rooms with little to no complexities, figuring out the square footage on your own is relatively simple with the right tools and simple math. But you can run into a little bit of trouble if your home is oddly shaped and has lots of spaces that are not exact squares or rectangles.

In this case, you might want to call in a contractor or appraiser who has experience in measuring the exact size of homes. This is definitely not a number you want to get wrong, because the answer you get will have a direct impact on the value of your home, as well as your listing price.