Square Footage Calculator – Calculate Area in Square Feet
The Square Footage Calculator makes it easy to find the area of any room, floor, wall, or outdoor space in square feet. Whether you're planning a flooring installation, painting project, or landscaping job, knowing the exact square footage helps you buy the right amount of materials. Simply enter your dimensions and shape, and get instant results in square feet, square meters, and square yards.
Select the shape of the area you want to measure.
Enter the length of the space in your chosen unit.
For rectangles enter width; for circles enter diameter; leave blank for triangles.
For triangles enter the perpendicular height. For L-shapes enter the height of the second rectangle.
Enter the length of the second section of the L-shape.
Enter the width of the second section of the L-shape.
Add extra percentage to account for cuts and waste. 10% is typical for most projects.
Your results will appear here
How to Use This Calculator
1. Select the shape that best matches your space — rectangle, circle, triangle, or L-shape. 2. Choose your preferred measurement unit (feet, inches, yards, or meters). 3. Enter the length and width (or diameter for circles, or height for triangles). 4. For L-shaped rooms, also fill in the second section's length and width. 5. Adjust the waste percentage slider if you want to add overage for material cuts (10% is recommended for most projects). 6. Your square footage, square meters, square yards, and total with waste will appear instantly in the results.
How Square Footage Is Calculated
Square footage is the area of a two-dimensional space measured in square feet. The formula depends on the shape of the space:
Rectangle or Square
The most common shape for rooms and floors. Multiply length by width:
Area = Length × Width
Circle
Used for circular patios, pools, or round rooms. Use the radius (half the diameter):
Area = π × Radius²
Triangle
Useful for angled corners or triangular sections. Multiply the base by the perpendicular height and divide by 2:
Area = 0.5 × Base × Height
L-Shape
Common for L-shaped rooms or open-plan spaces. Break the shape into two rectangles and add their areas:
Area = (Length₁ × Width₁) + (Length₂ × Width₂)
Unit Conversions
The calculator automatically converts your result into multiple units:
- Square Feet to Square Meters: multiply by 0.0929
- Square Feet to Square Yards: divide by 9
- Inches to Feet: divide by 12 before calculating
- Meters to Feet: multiply by 3.28084 before calculating
Why Add a Waste Factor?
When ordering materials like tiles, hardwood flooring, carpet, or wallpaper, professionals always add extra to account for cuts, breakage, and pattern matching. A 10% overage is standard for most projects, while intricate tile patterns or diagonal installations may need 15–20%.