Square Footage Calculator

Calculating the square footage of a room or building is an important part of many real estate and construction projects. This information can be used to estimate the cost of construction materials, labor, and other expenses associated with a project. Our calculator also provides the cost per square foot/metre, which can be helpful in budgeting and comparing the costs of different projects.

Square Footage and Cost per Square Foot/Metre Calculator
Side Length
Inner Length
Inner Width
Border Width
Side a
Side b
Side c
Outer Diameter
Inner Diameter
Radius r1
Radius r2
Altitude (Height)
Angle (θ, Radians)
Price per Square Foot
Square Footage ft2
Cost(at $ per square feet)

Please provide a rating, it takes seconds and helps us to keep this resource free for all to use

[ 1 Votes ]

The Formula

The formula for calculating the square footage of a room or building is:

Square Footage = Length x Width

For example, if a room is 12 feet long and 10 feet wide, the square footage would be:

Square Footage = 12 x 10 = 120 square feet

To calculate the cost per square foot/metre, you will need to know the total cost of the project and the total square footage. The formula is:

Cost per Square Foot/Metre = Total Cost / Total Square Footage

For example, if a project costs $50,000 and the total square footage is 1,500, the cost per square foot would be:

Cost per Square Foot = $50,000 / 1,500 = $33.33 per square foot

Or, if you prefer to use square metres:

Cost per Square Metre = Total Cost / Total Square Metres

It's important to note that the cost per square foot/metre can vary greatly depending on the materials used, labor costs, and other factors associated with a project.

Real-life Example

Let's say you are planning to build a new addition to your home. You want to know the square footage of the addition and the estimated cost per square foot. The addition is 20 feet long and 15 feet wide, making the total square footage 300 square feet. You receive an estimate from a contractor for $75,000 for the entire project, including materials and labor. To calculate the cost per square foot:

Cost per Square Foot = $75,000 / 300 = $250 per square foot

Based on this calculation, you can decide if the cost fits within your budget or if you need to consider alternative materials or construction methods to lower the cost per square foot.


Calculating the square footage and cost per square foot/metre can be a helpful tool in real estate and construction projects. Our calculator simplifies this process for you, allowing you to easily estimate the costs associated with your project. Keep in mind that the cost per square foot/metre can vary greatly based on a number of factors, so it's important to do your research and get multiple estimates before committing to a project.

Math Calculators

You may also find the following Math calculators useful.