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.

The mu (亩) is a traditional Chinese unit of area equal to approximately 666.67 square meters, used extensively in Chinese agriculture, rural land contracts, and property records. Farmland in China is almost always measured in mu, and government policies regarding grain production quotas reference this unit. One mu equals roughly 0.1647 acres or about 7,176 square feet.