Square Footage Calculator
Calculate square footage from a rectangular length and width, optionally totaled across multiple identical sections.
How It's Calculated
Formula
\text{areaSquareFeet} = (\text{length} \times \text{feetPerUnit}) \times (\text{width} \times \text{feetPerUnit}) \times \text{quantity}Square Footage calculates area FROM a rectangular length and width — this is different from Area Converter, which converts an existing area quantity between units. Length and width are each normalized into feet first (1 inch = 1/12 foot; 1 meter = 1/0.3048 feet), then multiplied together to get the area of one section in square feet, then multiplied by the quantity of identical sections. Square meters is reported as a secondary output, derived from square feet using the exact factor 1 ft² = 0.09290304 m². Length, width, and quantity must all be positive; quantity must be a whole number.
Worked Examples
10 ft x 12 ft room
- Length and width are already in feet: 10 ft, 12 ft.
- Area: 10 x 12 = 120 sq ft.
- Square meters: 120 x 0.09290304 = 11.148365 sq m.
10 ft x 12 ft room, 3 identical sections
- Area of one section: 10 x 12 = 120 sq ft.
- Total across 3 sections: 120 x 3 = 360 sq ft.
Frequently Asked Questions
How is this different from the Area Converter?
Square Footage calculates area from a length and width you measured. Area Converter instead takes an area value you already have and converts it between units (for example, square meters to acres). Use Square Footage when you have dimensions; use Area Converter when you already have an area figure.
Can I enter length and width in different units?
No. Both length and width use the same selected unit (feet, inches, or meters) in one calculation. Convert one of them first if your measurements are in different units.
What is the quantity field for?
Quantity totals the area across multiple identical sections of the same length and width, such as several identical rooms or tiles. It must be a whole number of 1 or more.
Why are negative or zero dimensions rejected?
A rectangle's length and width must be positive to have a defined physical area; zero or negative values are not valid measurements.