The square centimeter (cm²) is a metric area unit equal to one ten-thousandth of a square meter, commonly used in medical reports, lab measurements, and small product specifications. Skin lesion sizes, fabric swatches, and circuit board components are often measured in square centimeters. One square centimeter equals exactly 0.155 square inches.

The square mile (mi²) is a large imperial area unit equal to 640 acres or about 2.59 square kilometers, used for measuring expansive territories like cities, counties, and national parks. Geographic data in the United States and United Kingdom frequently references square miles when describing regions, especially in population density calculations. One square mile equals exactly 2.58999 square kilometers.