Square Footage Calculator

Get the Square Feet of an Area

Optionally enter the price per square foot

Material Estimate:

Using the Square Footage Calculator

This calculator is perfect for finding the square footage of any area, especially for construction, home remodeling, and renovation projects such as carpeting, hardwood flooring, tiling, framing, drywalling, painting, and gardening material estimates. Determine the total price of the project by including the price per foot.

Calculate the square footage for imperial measurements, metric measurements, or a mix of imperial and metric measurements. The calculator accepts inches, feet, yards, centimeters, and meters.

How to Find Square Footage

Square footage is just an area, measure in feet. Finding square feet is just like finding an area, by multiplying the length times the width. For finding the square footage of inches or another unit of measure, first convert the length and width measurements to feet, then multiply.

  • Measure the length and width of the area. If the area is not a simple shape, break the area into manageable parts and calculate the square feet of each part separately and then add that together. There is a great Wiki How article that details this process nicely. For example, if you are measuring a floor of your home, consider determining the square feet of each room, and then add all of the rooms square footage together to derive the total area.
  • Convert these measurements to feet if they aren’t already. Convert inches to feet, convert yards to feet, or convert meters to feet
  • Multiply the length in feet times the width in feet

Calculate the square footage of a square area


square footage (ft2) = length x width



square footage (ft2) = length x width

Calculate the square footage of a border

Rectangular Border

Using measurements in feet:

outside (ft2) = length x width
inside (ft2) = (length – (2 x border)) x (width – (2 x border))

border (ft2) = outside (ft2) – inside (ft2)

Calculate the square footage of a circle area


square footage (ft2)= pi x (diameter / 2)2

pi = 3.14159265359

Calculate the square footage of a triangle area


square footage (ft2) = (1/4) x
(a+b+c) x (b+c-a) x (c+a-b) x (a+b-c)

Measuring the Square Feet of a Home or Residence

If you’re measuring the square footage of a home or residence, there are some special considerations that apply to determine inhabitable square footage. The square footage of a home helps determine the market value and price of a home and also helps buyers understand the size of the home. This guide explains how to measure the complete square footage of your home. Only rooms that are livable, with finished walls, floor, and ceiling, count toward the finished area of the home. To calculate the total area, get the square footage of each finished room and add together. The calculator above can help determine the square feet of each room, then simply add all of the room’s areas together.

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