How do I calculate square footage of a room?

For a rectangular room, multiply the length by the width (both in feet). For example, a room that is 12 feet long and 10 feet wide has 120 square feet. For irregular shapes, break the room into rectangles, calculate each section separately, and add them together.

How do I convert inches to feet for square footage?

Divide the measurement in inches by 12 to get feet. For example, 144 inches = 12 feet. If your room is 144 inches by 120 inches, that is 12 feet by 10 feet = 120 square feet. You can also enter measurements in inches directly and the calculator will convert automatically.

How much square footage do I need for flooring?

Measure the square footage of each room you want to floor, add them together, then add 10% for waste and cuts. For example, if your rooms total 500 square feet, order 550 square feet of flooring. For diagonal installations or complex patterns, add 15% instead.

How do I calculate square footage of an L-shaped room?

Divide the L-shape into two rectangles. Measure each rectangle separately (length x width), then add the two areas together. For example, if one section is 10x12 ft (120 sq ft) and the other is 8x6 ft (48 sq ft), the total is 168 square feet.

How many square feet is a 10x10 room?

A 10x10 room is exactly 100 square feet. Common room sizes: 10x10 = 100 sq ft (small bedroom), 12x12 = 144 sq ft (average bedroom), 15x20 = 300 sq ft (large living room), 20x20 = 400 sq ft (great room). A standard two-car garage is typically 400-576 square feet.

Tools

Square Footage Calculator

Calculate the square footage of any room, floor, or area instantly. Supports rectangles, triangles, circles, and L-shaped rooms. Perfect for flooring, painting, tiling, and real estate.

Measurement unit:

Shape

Length (ft)

Width (ft)

Waste / Overage Factor (%)

Add extra for cuts and waste. Recommended: 10% for straight installations, 15% for diagonal or pattern.

10%

Formulas Used

Rectangle: Area = Length × Width
Triangle: Area = ½ × Base × Height
Circle: Area = π × Radius²
L-Shape: Area = (Section 1 L × W) + (Section 2 L × W)
With waste: Order Amount = Area × (1 + Waste%)

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How to Use the Square Footage Calculator

Calculate the square footage of any room or area in three simple steps.

1
Select your room shape
Choose from rectangle (most rooms), triangle, circle, or L-shape. Most rooms are rectangular.
2
Enter your measurements
Input the length and width in feet or inches. For L-shaped rooms, enter the dimensions of each section separately.
3
Read your result
The calculator instantly shows the total square footage. Use this number for flooring, paint, tile, or real estate estimates.
4
Add a waste factor
For flooring and tile projects, add 10% to your square footage to account for cuts, waste, and future repairs.

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Square Footage Calculator

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How to Use the Square Footage Calculator

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