How to measure a room
Measure from wall to wall along the floor, at the widest point of each side. Use a tape measure or a laser measure and write down the length and the width in the same unit.
Measure the finished wall surface, not the studs. If the room is not a perfect rectangle, measure at two or three places and use the average, or split the room into rectangles as shown below.
Area is length times width. A 12 ft × 15 ft room is 180 ft² and a 4 m × 5 m room is 20 m².
How to calculate the square footage of an L-shaped room
Split the L into two rectangles with one imaginary line, measure each one and add the two areas. In the calculator, enter each rectangle as its own room and read the total.
Example: the long part is 12 ft × 10 ft = 120 ft² and the short leg is 8 ft × 6 ft = 48 ft². The L-shaped room is 168 ft², or 15.61 m². Take care that the two rectangles do not overlap, or you will count the corner twice.
What counts in a home’s square footage
Square footage usually counts finished, heated living space such as bedrooms, living rooms, kitchens, bathrooms and hallways. Rules differ by country and by agent, so ask what a listing counts.
Garages, unfinished basements, porches and patios are normally left out of the living area, and some places count only space with a ceiling height of about 7 ft (2.1 m) or more. Wall thickness is counted in some measurements and not in others.
To compare an apartment listed in square meters with one in square feet, multiply square meters by 10.7639. See the square meters to square feet converter.
Room area calculator: FAQ
How do I calculate the area of a room?
Multiply length by width. A 12 ft × 15 ft room is 180 ft², which is 16.72 m². In meters, a 3.5 m × 4 m room is 14 m², which is 150.69 ft².
How do I convert square meters to square feet?
Multiply by 10.7639. For example, 20 m² is 215.28 ft². To go the other way, multiply square feet by 0.092903: 1,000 ft² is 92.9 m².
How do I calculate the area of an L-shaped room?
Split the L into two rectangles, find the area of each and add them. An L made of a 12 ft × 10 ft block and an 8 ft × 6 ft block is 120 + 48 = 168 ft², which is 15.61 m².
How much is a 10 ft × 10 ft room in square meters?
A 10 ft × 10 ft room is 100 ft², which is 9.29 m² (3.05 m × 3.05 m).
Is the calculator free and private?
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