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How to Use Our Square Footage Calculator

3 min read

How to Use Our Square Footage Calculator

Whether you are buying flooring, estimating paint, or listing a property, knowing your exact square footage is essential. Our Square Footage Calculator handles the math for any shape.

Square Footage Calculator

ft
ft

Square Feet

300 sq ft

Square Yards33.33 sq yd
Square Meters27.87 sq m
Acres0.01
Perimeter70 ft
Total Cost$0

Basic Rectangular Rooms

For standard rectangular rooms, enter:

  • Length -- Measure wall to wall in feet.
  • Width -- Measure the perpendicular wall.

The calculator multiplies length by width to give you the square footage. A room that is 12 feet by 15 feet is 180 square feet.

Irregular Shapes

For L-shaped rooms, rooms with alcoves, or other irregular shapes, break the space into rectangles. Calculate each rectangle separately and add them together. For example, an L-shaped room might be a 10x12 rectangle plus a 6x8 rectangle: 120 + 48 = 168 square feet.

Common Applications

  • Flooring: Order materials based on total square footage plus 10% for waste and cuts.
  • Real estate: Verify listing accuracy or estimate your home's livable space.
  • HVAC sizing: BTU calculations for heating and cooling depend on room size.
  • Gardening: Calculate garden bed area for soil, mulch, or sod estimates.

Measuring Tips

Measure in inches and convert. For precision, measure in inches and divide by 12 to get feet. A room that is 147 inches by 183 inches is 12.25 x 15.25 feet = 186.8 square feet.

Include closets when measuring for real estate purposes but exclude them when measuring for flooring in the main room.

Related Calculators

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Tile Calculator

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