Kilogram per metre cubed

Kilogram per cubic metre is an SI derived unit of density, defined by mass in kilograms divided by volume in cubic metres. The official SI symbolic abbreviation is kg·m⁻³, or equivalently either kg/m³ or ${\displaystyle {\tfrac {\text{kg}}{{\text{m}}^{3}}}\!}$.

1 kg/m³ is equivalent to:

1 g/cm³ = 1000 kg/m³ = 1,000,000 g/m³ (exactly)

1 lb/ft³ ≈ 16.02 kg/m³ (approximately)

1 oz/gal ≈ 7.489 kg/m³ (approximately)

The kilogram was originally based on the mass of one litre of water, thus the density of water is about 1000 kg/m³ or 1 g/cm³. In chemistry, g/cm³ is more commonly used.

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