Square footage = length × width in feet. A 20 × 15 ft room is 300 ft², which is 27.87 m² or 33.3 square yards. Split an L-shaped room into two rectangles and add them; a circle is π × diameter² ÷ 4. Add 5 to 10% for flooring or tile waste.
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Square Footage Calculator
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Total area
300.00ft²
In square meters
27.87 m²
Square yards
33.33 yd²
Acres
0.0069 acres
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An L-shaped floor, 20 × 15 ft plus 10 × 8 ft, to be tiled with 10% waste at 4 per ft²:
Main part = 20 × 15 = 300 ft²
Second part = 10 × 8 = 80 ft²
Total = 380 ft² (35.30 m², 42.2 yd²)
With 10% waste = 418 ft²; cost = 418 × 4 = 1,672
Common Room Sizes
Room
Size
Square feet
Square meters
Small bedroom
10 × 10 ft
100 ft²
9.29 m²
Bedroom
12 × 12 ft
144 ft²
13.38 m²
Main bedroom
14 × 16 ft
224 ft²
20.81 m²
Living room
16 × 20 ft
320 ft²
29.73 m²
One-car garage
12 × 22 ft
264 ft²
24.53 m²
Two-car garage
24 × 24 ft
576 ft²
53.51 m²
How to Measure a Room for Square Footage
Measure the longest length and width at floor level with a tape, to the nearest inch.
Turn inches into feet: divide by 12 (10 ft 6 in is 10.5 ft).
Multiply length × width for the square footage.
Split L-shaped or irregular rooms into rectangles, work out each one and add them.
For flooring or tile, add 5 to 10% for cutting waste.
Frequently Asked Questions
How do I calculate square footage?
Measure the length and width in feet and multiply them. A 12 × 10 ft room is 120 ft². If you measured in inches, multiply and divide by 144.
How do I find the square footage of an L-shaped room?
Split it into two rectangles, work out each one and add them. A 20 × 15 ft area plus a 10 × 8 ft area is 300 + 80 = 380 ft².
How many square feet are in a square meter?
One square meter is 10.764 ft², and one square foot is 0.0929 m².
How many square feet are in an acre?
An acre is 43,560 ft². A square yard is 9 ft², so an acre is 4,840 square yards.
How do I get the square footage of a house?
Add up the area of each room, or measure the outside of each floor and multiply. Builders usually quote the area to the outside of the walls, so it is larger than the rooms added together.
How big is 60 square feet?
About 5.6 m², the size of a 6 × 10 ft room or a square about 7.7 ft on each side. That is a typical small bathroom or walk-in closet.
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