Square Footage Calculator
Calculate area for flooring, landscaping, or renovations.
How to Calculate Square Foot: A Comprehensive Guide
Whether you are planning to install new hardwood floors, tile a bathroom, or seed a lawn, knowing how to calculate square footage is the first step toward a successful project. Square footage is a measurement of area, typically used for flat surfaces.
The Basic Square Foot Formula
For a standard rectangular or square room, the calculation is simple geometry:
Length (ft) × Width (ft) = Total Square Footage
For example, if you have a room that is 12 feet long and 10 feet wide, the calculation is 12 × 10 = 120 square feet.
Steps to Measure Your Space
- Clear the Area: Ensure you can reach the corners of the room for an accurate measurement.
- Measure Length: Use a tape measure to find the distance from one wall to the opposite wall. Round to the nearest inch or decimal point.
- Measure Width: Measure the distance of the adjacent wall.
- Multiply: Multiply the two numbers together to get your base area.
Handling Irregular Shapes
Not every room is a perfect rectangle. If you have an "L-shaped" room or a space with alcoves, the best approach is to break the area into smaller, manageable rectangles. Calculate the square footage of each section individually and add them together at the end.
Why Include a Waste Factor?
In the flooring and construction industry, it is standard practice to order more material than the exact square footage of the room. This is called a "Waste Factor." Typically, 10% is added to account for:
- Cutting tiles or planks to fit corners.
- Accidental breakage during installation.
- Pattern matching (especially for patterned carpet or tile).
- Future repairs or replacements.
Example Calculation
Imagine you are tiling a kitchen that is 15 feet long and 12 feet wide. The price of the tile is $5.00 per square foot.
- Base Area: 15 × 12 = 180 sq ft.
- 10% Waste: 180 × 0.10 = 18 sq ft.
- Total Needed: 180 + 18 = 198 sq ft.
- Total Cost: 198 × $5.00 = $990.00.