Square Footage Calculator
Enter length and width in feet or inches to get square feet, square meters, and square yards. Works for rectangles, circles, triangles, and irregular rooms split into several areas.
Last updated: September 24, 2026
Enter Measurements
ft
ft
Area: 120 sq ft
Results
Total Area
120
square feet
11.15
square meters
13.33
square yards
How to Use This Calculator
1
Choose Unit & Shape
Select your measurement unit (feet, inches, meters) and the shape of your area.
2
Enter Dimensions
Input the length and width (or other dimensions based on shape).
3
Add More Areas
For complex spaces, add multiple sections and they'll be totaled automatically.
How We Calculate
Rectangle / Square
Area = Length × Width Example: 10 ft × 12 ft = 120 sq ft
Inches: 154 in × 135 in = 20,790 in² ÷ 144 = 144.4 sq ft
Triangle
Area = (Base × Height) ÷ 2 Example: (10 ft × 8 ft) ÷ 2 = 40 sq ft
Circle
Area = π × Radius² Example: π × 5² = 78.54 sq ft
Trapezoid
Area = ((Top + Bottom) ÷ 2) × Height Example: ((8 + 12) ÷ 2) × 10 = 100 sq ft
Frequently Asked Questions
For a rectangle or square, multiply length by width. For example, a 10 ft × 12 ft room equals 120 square feet. See How We Calculate for the formula used by each shape.
A 12×12 room is 144 square feet. Simply multiply 12 × 12 = 144 sq ft. This is equivalent to about 13.4 square meters or 16 square yards.
Multiply the two inch measurements together, then divide by 144. For example, 154 in × 135 in = 20,790 in² ÷ 144 = 144.4 sq ft. To get the answer instantly, switch the unit to Inches and enter both numbers.
1 square yard equals 9 square feet (3 ft × 3 ft = 9 sq ft). To convert square feet to square yards, divide by 9. Carpet is often priced per square yard.
Measure each room's length and width, add the areas together, then add 10-15% for waste and cuts. If you measured in inches, divide each room's square inches by 144 first. Use our Tile Calculator or Flooring Calculator for material quantities including the waste allowance.