Square Footage Calculator
Calculate area of rooms, triangles and circles in square feet, metres and yards.
Last updated: August 2026
Area
200 ft²
Square metres
18.6 m²
Square yards
22.2 yd²
Acres
0.0046
For irregular rooms, split into rectangles and add the results.
How it works
Rectangle: L × W. Triangle: ½ × b × h. Circle: π × r². 1 m² = 10.764 ft².
Example: 20 ft × 10 ft room = 200 ft² ≈ 18.6 m².
Frequently Asked Questions
How do I calculate the area of a room?
Multiply length by width. A 20 ft × 10 ft bedroom is 200 square feet, about 18.6 square metres.
How many square feet is a square metre?
One square metre is 10.764 square feet. A 100 m² apartment is about 1,076 ft².
What is the area of a circle?
π × radius². A circular gazebo with a 5 ft radius covers about 78.5 square feet.
How much flooring or paint should I buy?
Multiply the room's square footage by the number of coats for walls, or add about 10% waste for flooring. A 200 ft² room needs roughly 220 ft² of tiles.