Construction
Square Footage Calculator
Room area in square feet, square yards, or square meters.
Measurement formulas
Rectangle: L × W
Triangle: 0.5 × Base × Height
Circle: π × (Diameter ÷ 2)²
Always order 10% extra
When buying flooring, tile, or wallpaper, add 10% to your measured area for cuts and waste. For complex tile patterns, use 15%.
Rough material cost estimates
- Hardwood flooring: $5–15/sq ft installed
- Luxury vinyl plank: $3–8/sq ft installed
- Carpet: $2–8/sq ft installed
- Paint: ~400 sq ft per gallon (one coat)
⚡ CalcWolf Insight
Average US home size in 2025 is 2,273 sq ft — down from a peak of 2,687 in 2015. Smaller homes are trending as remote work declines and urban demand rises.
Frequently asked questions
How do I calculate square footage of a room?▾
Measure length × width in feet. A 14ft × 11ft room = 154 square feet.
How do I convert sq ft to sq meters?▾
Multiply by 0.0929. So 200 sq ft = 18.58 m².
How much extra flooring should I order?▾
Add 10% for straight-lay patterns, 15% for diagonal or herringbone.
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