What is Square Footage Calculator?
The Square Footage Calculator simplifies the process of finding the area of any room, wall, or plot of land in square feet. It is an essential tool for home renovations, flooring installation, painting projects, and real estate listings. The calculator supports multiple area shapes, including rectangles, circles, and triangles, allowing you to estimate materials precisely.
Formula
Rectangular Area = Length (feet) * Width (feet)
Circular Area = pi * Radius (feet)^2
Benefits of Using Square Footage Calculator
Renovation Accuracy - Know exactly how much flooring, carpet, or tile to purchase.
Multi-Room Totals - Sum areas of multiple rooms to find a home's total square footage.
Waste Allowance Factor - Helps add a standard 10% safety margin for cutting loss.
Unit Conversions - Converts square feet to square yards, meters, and acres.
Pro Tip: When buying tiles, paint, or wood flooring, always purchase 10% to 15% more materials than your calculated square footage to account for cutting waste, mistakes, and corners.
Frequently Asked Questions
Measure the length and width of the room in feet. Multiply these two numbers together to find the square footage (e.g. 10 ft x 12 ft = 120 sq ft).
Divide the inches by 12 to convert them to feet before multiplying, or multiply the inches first and divide the final result by 144.
Split the room into two smaller rectangular shapes, calculate the square footage of each rectangle separately, and add the two totals together.
One gallon of paint typically covers about 350 to 400 square feet of wall space with a single coat.
Measure the diameter in feet, divide by 2 to get the radius, square the radius, and multiply by 3.14159.
Reviewed by Rahul Kumar | Founder, WPFixHub
Updated: August 2026