• For area the square hectometre (hm²) is a common unit. It is also known by the name hectare (ha), meaning 100 ares (100 a). The are is a measurement of area the size of 1 decametre by 1 decametre, which is 10 metres by 10 metres. Hence 100 are equals an area with dimensions 100 m by 100 m — 1 hectometre by 1 hectometre, the square hectometre — equalling 10,000 square metres (10,000 m²).
• For volumes the cubic hectometre (hm³) is also used, 100 m by 100 m by 100 m equalling 1,000,000 cubic metres (1,000,000 m³).

See also

• SI
• SI prefix
• hecto-
• Metric System
• For length: 1 E+2 m and Orders of magnitude (length)
• For surface: 1 E+4 m² and Orders of magnitude (area)
• For volume: 1 E+6 m³ and Orders of magnitude (volume)
• Conversion of units, for comparison with other units