How to Calculate Square Footage for Any Project
Learn the simple math behind measuring rooms, decks, and yards. Plus, use our automatic square foot calculator.
Why Square Footage Matters
Almost every home improvement project starts with square footage. Whether you are buying paint, flooring, mulch, or grass seed, knowing your total area ensures you order the right amount of material.
The Basic Formula
For a standard rectangle, the formula is simple: Length (ft) × Width (ft) = Square Footage (sq ft)
If your room is 10 feet long and 12 feet wide, your area is 120 square feet.
Handling Inches
Many rooms aren't perfect round numbers. If your room is 10 feet 6 inches, remember that 6 inches is 0.5 feet. Our calculator below handles those inches for you automatically.
Complex Shapes
If you have an L-shaped room, the easiest way to find the area is to divide it into two rectangles, calculate them separately, and add them together.
Pro Tip
Always add a 10% waste factor to your final square footage when ordering materials like tile or hardwood. It's better to have half a box left over than to run out during the final row!
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