Square Footage Calculator
Calculate area for flooring, paint, and renovation projects.
How to Calculate Square Footage
Square footage is the measurement of an area expressed in square feet. It is the most common unit of measure for residential and commercial real estate in the United States. To calculate square footage for a rectangular room, you simply multiply the Length (in feet) by the Width (in feet).
The Formula:
Length (ft) × Width (ft) = Area (sq ft)
Why Include a Waste Factor?
When ordering materials like hardwood flooring, tile, or carpet, it is critical to order more than the exact net area of the room. This accounts for pieces that must be cut to fit edges, mistakes made during installation, and damaged materials. A 10% waste factor is the industry standard for most rectangular rooms, while 15-20% is recommended for rooms with many corners or when laying tile on a diagonal.
Measuring Irregular Rooms
If your room is not a perfect rectangle (e.g., L-shaped or has alcoves), the best method is to divide the space into smaller, manageable rectangles. Calculate the square footage of each smaller section separately and then add them together to get the grand total.
Real-World Example
Imagine you are tiling a kitchen that is 12 feet long and 15 feet wide.
- Net Area: 12 × 15 = 180 sq ft.
- With 10% Waste: 180 + 18 = 198 sq ft.
- Material Cost: If the tile costs $5.00 per sq ft, your estimated cost would be 198 × $5.00 = $990.00.