The acre is an imperial unit of area equal to 43,560 square feet or about 4,047 square meters, predominantly used in the United States, United Kingdom, and former British colonies for land measurement. Real estate listings, farmland boundaries, and suburban lot sizes in these regions are conventionally expressed in acres. One acre is roughly equivalent to 90% of a standard football pitch.

The square foot (ft²) is an imperial area unit equal to a square measuring one foot on each side, the standard measurement for home sizes, office space, and rental properties in the United States. Real estate listings in America almost always quote living space in square feet, making it one of the most practically relevant area units. One square foot equals exactly 0.0929 square meters.