What Is a Square Footage Calculator?
A square footage calculator measures the area of a room, floor, or wall by multiplying length by width. Whether you are buying flooring, estimating paint, or comparing apartment sizes, square footage is the standard unit used in real estate and construction across the United States. This tool lets you add multiple areas to get one combined total in both square feet and square meters.
How to Calculate Square Footage
For a rectangular space, square footage is simply length multiplied by width. For example, a room that is 20 feet long and 15 feet wide is 300 square feet. When measuring in inches, divide your result by 144 to convert square inches to square feet. For irregular spaces, break the area into smaller rectangles, calculate each one, and add them together — exactly what the "add another area" feature does.
Why Square Footage Matters
Square footage affects home value, heating and cooling costs, and the amount of material you need for a project. Flooring, paint, and tile are all purchased by the square foot, so knowing your exact area prevents both overbuying and running out of materials mid-project. In real estate, homes are often priced per square foot, making this a key number for buyers and sellers.
Measuring Multiple Rooms
Most projects involve more than one space. Measure each room's length and width individually, then add each rectangle as a separate area in the calculator. The tool totals everything for you automatically and shows a per-area breakdown so you can double-check each measurement.
Square Feet to Square Meters
One square foot equals about 0.0929 square meters. This calculator converts automatically, which is helpful if you are following a plan that uses metric measurements or comparing international property listings.
FAQs
How do I measure an L-shaped room?
Divide it into two rectangles, measure each, and add them as separate areas in the calculator.
Does square footage include walls?
For room area, measure inside wall to inside wall. For paint, you will calculate wall surface area, not floor area.
Planning a renovation? Estimate materials with our flooring calculator, paint calculator, or tile calculator.