How to calculate square feet using one easy formula

Square footage is simply the amount of flat space that covers an area. For example, say you know that your room is 8 feet wide by 12 feet long. You know the width and length, but what about how much surface area you’re looking at? How can you determine if your furniture will fit comfortably in the space? 

The square footage will tell you how much surface area you have to work with. This calculation can help you make decisions about what size rug to buy, or even help you figure out if your room can fit a full or queen size bed based on how much usable square footage you have available and how much square footage your bed’s footprint will cover.

Tip: Knowing the measurements of your furniture can help you plan the best arrangement for your unique space. A footprint is the amount of space an item will take up on the ground—just like your footprint, a piece of furniture will cover a certain area of your room. 

To calculate the square footage of any area, all you need to do is multiply the length and the width of the area (how tall x how wide). The unit of measure will impact how you calculate square footage because, well, square feet is the most common measurement used in the United States when it comes to room sizes and DIY home supplies. However, it’s easy to translate other units of measure like inches or yards using the basic formula.

Basic formula for square feet

To calculate feet squared (or sq. ft.  for short), determine the length and width of the area you are working with, measured in feet. Multiply the length by the width and you’ll have the square feet. Here’s a basic formula you can follow:

Length (in feet) x width (in feet) = area in sq. ft.

Tip: If you can’t picture what a square foot is, try drawing a square that is 1 foot tall by 1 foot wide—you’ve got one square foot! Many of those squares stacked up against one another equal a whole wall, floor, sheet of fabric, wall paper, etc. You’re measuring how much a total area covers instead of only how tall or how wide. 

Other units of measure

• If you need to translate the square footage area into square inches (more common for smaller items), follow the basic equation, but multiply the length and width measurements by 12 (because there are 12 inches in one foot).

• If you need to translate the square footage area into square yards (more common for fabrics), follow the basic equation, but divide the length and width measurements by 3 (because there are 3 feet in one yard).

• If you need to calculate the area in square meters (for the metric system), follow the basic equation, but divide the length and width measurements by 0.3 (because there are 0.3 meters in one foot).

• Rectangular rooms: To calculate the area of a room or area with a square or rectangle shape, simply follow the formula.

• Rooms with closets: Rooms with closets are like rectangular rooms with small rectangular add ons. Calculate the square footage of each rectangle, and add them together.

• Odd-shaped rooms: The standard tool for area measure is something you can apply even to odd-shaped rooms. All you need to do is break the room down into separate areas that are easy to calculate on their own and then add up the results. If your room has a lot of angles, use this formula for a triangle—it’s just a rectangle or square cut in half!

Length (in feet) x width (in feet) ÷ 2 = area in sq ft

The term “usable square footage” is usually used in a commercial real estate setting to describe the amount of square footage a tenant can actually use, excluding common areas like stairwells, hallways, and lobbies. 

In a residential real estate context, your usable square footage is the surface area of your personal space in the household, versus the common areas like hallways, storage closets, and shared spaces such as kitchens and living rooms.

Bungalow offers private rooms in shared homes that are more affordable than solo housing options in the same neighborhoods. Wifi, utilities, and monthly cleaning are set up before you move in so that coliving is seamless. Unlike other shared housing options, Bungalow vets all residents and helps you match with roommates who share your living preferences and interests. Find your next home on Bungalow.