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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.

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.

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