How to use this square footage calculator
Find rectangular area in square feet, square meters and square yards. Start with the labeled example values, then replace them with the figures for your problem. Keep units consistent. Results update as you type. If an entry is invalid, the result is cleared and the page explains what needs attention, rather than showing a stale answer.
Formula and calculation method
Rectangle area equals length multiplied by width. Multiply by the number of identical rectangles for a repeated layout. One square yard equals nine square feet. One square foot equals 0.09290304 square meters. A square measurement describes area and is different from a linear dimension or a cubic volume.
Worked example
A rectangle 12 feet long and 10 feet wide covers 120 square feet. Two matching rectangles cover 240 square feet, or approximately 22.2967 square meters. If different rooms have different sizes, calculate them separately and add their areas rather than averaging their lengths and widths.
Assumptions and limitations
This model does not subtract openings or add purchasing waste. Split irregular shapes into non-overlapping rectangles, and subtract excluded rectangular areas separately. For dimensions with inches, convert inches to a fraction of a foot first: six inches is 0.5 feet. Quantity must be a positive whole number.
Check and keep your result
Check the example by hand before applying the result to your own figures. Download the result to retain the inputs with the output, or use Print for a paper copy. Calculations run locally in your browser and entries are not sent to our server. The website’s advertising services operate separately; see our privacy policy.
Created and calculation-tested by Velour Trends · Updated 8 November 2026. No independent professional review is claimed. Report a calculation issue.