The square meter (m²) is the SI base unit of area, equal to a square measuring one meter on each side, used worldwide for real estate, construction, and land surveying. Apartment sizes, office floor plans, and construction costs are almost universally quoted in square meters outside the United States. One square meter equals approximately 10.764 square feet.

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.