### Things You'll Need

Tape measure

Calculator

When purchasing new flooring or wallpaper for a room, you need to know the square footage of the floors or walls. When ordering landscaping material for your yard, you need to know the square footage of the spaces you want to fill. No matter the size or shape of the area you need to measure, you can easily calculate square footage by performing some simple calculations. Armed with a thorough understanding of how to calculate square footage, you will be able to make accurate measurements for many home improvement materials, including carpeting, paint and tile.

## Square or Rectangular Areas

## Step 1

Stretch your tape measure across the width of the area you wish to measure. Read the measurement in feet. This number will be your width measurement.

## Step 2

Stretch the tape measure across the length of the area you wish to measure. Read the measurement in feet. This number will be your length measurement.

## Step 3

Multiply the measured width by the measured length. The resulting product is the square footage of your square-shaped or rectangle-shaped area.

## Triangular Areas

## Step 1

Stretch your tape measure across one edge of the triangle-shaped area you wish to measure. Read the measurement in feet. This will be the measurement of the base of your triangle.

## Step 2

Set the end of the tape measure at the base of the triangle-shaped area and stretch it across the height of the triangle. This measurement will be the height of your triangle.

## Step 3

Multiply the measured base by the measured height. Then divide your calculated product by two. The resulting number will be the square footage of your triangle-shaped area.

## Circular Areas

## Step 1

Measure in feet across the widest width of your circle-shaped area. Read the measurement in feet. This number is the circle's diameter.

## Step 2

Multiply the measured diameter by itself. Then, multiply this calculated product by 3.14.

## Step 3

Divide your calculated result from the previous step by four. This number is the square footage of your circle-shaped area.

### Tip

If the area needing measured is an irregular shape, you can still calculate the square footage. Break your area down into sections of basic shapes, and calculate the square footage of the separate shapes. Then, add the measurements of the shapes together to find the square footage of the entire area.

To calculate cubic footage, you will need to know the measurement of the height of your room. Multiply this height measurement by your square footage measurement. This will give you the cubic footage of your room.

When listing your home for sale, you will need to measure the square footage of every room in your home. This will enable you to list as accurately as possible the size of your home's interior.

There are 43,560-square feet in an acre. To measure acreage of your lot, you should first measure the square footage. Then, divide the square footage by 43,560. The resulting number will be your lot in acres.