Square Footage Calculator
Calculate total square feet (sq ft), square meters (sq m), and square yards for flooring, carpet, paint, and construction projects across multiple rooms.
How It Works
Formula
Square Footage (sq ft) = Length (ft) × Width (ft) | With Waste = Total Sq Ft × (1 + Waste % / 100) Worked Example
A room measuring 14 ft by 12 ft equals 168 sq ft (18.67 sq yd or 15.61 sq m). Adding a 10% flooring wastage allowance gives 184.8 sq ft to purchase.
Complete Guide to Calculating Square Footage
Accurately calculating square footage is crucial when estimating materials for home improvements—including hardwood flooring, laminate, carpet, ceramic tiles, sod, wallpaper, and interior paint. Underestimating leads to project delays, while overestimating results in non-refundable leftover materials.
Calculating Different Geometric Layouts
Not all rooms or outdoor plots are simple rectangles:
1. Rectangular and Square Spaces
$$\text{Area} = \text{Length} \times \text{Width}$$ Example: A $15\text{ ft} \times 11\text{ ft}$ living room has an area of $165\text{ sq ft}$.
2. Triangular Areas (Gables, Corner Plots)
$$\text{Area} = \frac{\text{Base} \times \text{Height}}{2}$$ Example: A corner garden bed with an $8\text{ ft}$ base and $6\text{ ft}$ height is $(8 \times 6) / 2 = 24\text{ sq ft}$.
3. Circular Areas (Fire Pits, Circular Patios)
$$\text{Area} = \pi \times r^2 \approx 3.1416 \times (\text{Radius})^2$$ Example: A circular patio with an $8\text{ ft}$ diameter has a $4\text{ ft}$ radius. Area $= 3.1416 \times 16 \approx 50.27\text{ sq ft}$.
4. Trapezoidal Areas
$$\text{Area} = \left(\frac{a + b}{2}\right) \times h$$ Where $a$ and $b$ are the lengths of the two parallel sides and $h$ is the perpendicular distance between them.
Unit Conversions Cheat Sheet
| From | To | Formula |
|---|---|---|
| Square Feet (sq ft) | Square Yards (sq yd) | Divide by 9 |
| Square Feet (sq ft) | Square Meters (sq m) | Multiply by 0.092903 |
| Square Inches (sq in) | Square Feet (sq ft) | Divide by 144 |
| Acres | Square Feet (sq ft) | Multiply by 43,560 |
Frequently Asked Questions
How do I calculate the square footage of a room?
Measure the length and width of the room in feet and multiply the two numbers together (Length × Width = Sq Ft). If your measurements are in inches, divide each measurement by 12 first, or multiply inches together and divide by 144.
How much extra flooring should I order for wastage?
Industry standards (TCNA and NWFA) recommend ordering 10% extra for standard rectangular rooms. For diagonal tile layouts, herringbone patterns, or rooms with many alcoves and curves, order 15% to 20% extra.
How do I convert square feet to square yards for carpeting?
Divide total square footage by 9 (since 1 yard = 3 feet, 1 sq yd = 3 × 3 = 9 sq ft). For example, 180 sq ft ÷ 9 = 20 sq yards.
How do I calculate square feet for an L-shaped room?
Divide the L-shape into two separate rectangles, calculate the square footage of each section individually, and add the two totals together.
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