Square Footage Calculator
Add each room or area — rectangles, triangles, circles or L-shapes — in feet and inches or meters. Get the total square feet, square meters, material with waste, and cost.
252 ft² = 252 ft²
48 ft² = 48 ft²
- Square meters
- 27.87 m²
- Square yards
- 33.33 yd²
- With 10% waste
- 330 ft²
- Acres
- 0.006887
| Area | ft² |
|---|---|
| Living room | 252 |
| Hallway | 48 |
Your areas are saved in this browser so you can come back to them.
How to calculate square footage
- Measure the length and width of each room in feet. Round up to the next inch.
- Convert inches to decimal feet: divide by 12 (10 ft 6 in = 10.5 ft).
- Multiply length × width for each rectangle.
- For L-shaped rooms, measure the full bounding rectangle and subtract the missing corner — or split it into two rectangles.
- Add all areas together, then add a waste allowance before you buy material.
Quick conversions
- 1 ft² = 144 in²
- 1 yd² = 9 ft²
- 1 m² = 10.764 ft²
- 1 acre = 43,560 ft²
Carpet is often priced per square yard: divide square feet by 9. Flooring boxes list coverage in ft² per box; divide your total with waste by that figure and round up.
Questions people ask
How do I calculate the square footage of a room?
Multiply the length by the width in feet. A 12 ft × 15 ft bedroom is 180 ft².
How do I measure an L-shaped room?
Split it into two rectangles and add them, or measure the full outer rectangle and subtract the missing corner. Choose "L-shape" to do the second method.
How much extra flooring should I buy?
Most installers add 5–10% for straight-laid planks or tile and 15% or more for diagonal or herringbone patterns, to cover cuts and breakage.
Does square footage of a house include the garage?
Usually not. In the US, listed living area (per ANSI Z765 guidance) counts finished, heated space above grade; garages, unfinished basements and porches are typically listed separately.
How many square feet is a 10 × 10 room?
100 ft², or about 9.29 m².
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