Unit I I base 1 ca 1 m2 1 m2 1 a 1 dam2 102 m2 1 ha 1 hm2 104 m2 100 ha 1 km2 106 m2 non-SI comparisons non-SI etric I base 0.00386102 sq mi 1 ha 104 m2 2.471 acre 1 ha 104 m2 107,639 sq ft 1 ha 104 m2 A hectare (symbol ha, ) is a unit of area equal to, or one square hectometre (100 metres, squared), and is commonly used for measuring land area. The hectare is used in most countries around the world, especially in domains concerned with land ownership, land planning, and man… (More on Hectare)