๐งฑ Density Converter
Convert between kg/mยณ, g/cmยณ, lb/ftยณ, lb/gal, and other density units in real time. Useful for materials science and chemistry homework, or checking the density specs of imported materials and liquids.
How to use
- Enter a value into any density unit field (kg/mยณ, g/cmยณ, lb/ftยณ, or lb/gal).
- The converted values appear instantly in the other unit fields.
How the calculation works
Density is mass per unit volume: density = mass รท volume. The SI unit is kg/mยณ, but a cubic metre is large, so g/cmยณ (the same as kg/L) is common. 1 g/cmยณ = 1,000 kg/mยณ. Water is about 1 g/cmยณ: denser materials sink in it and less dense ones float. Density relative to water is called specific gravity, and numerically it is almost the same as the density in g/cmยณ. lb/ftยณ is about 16.02 kg/mยณ, and lb/gal (US gallon) about 119.8 kg/mยณ. Every conversion goes through kg/mยณ.
Worked example
Water (1 g/cmยณ) in each unit kg/mยณ: 1,000 lb/ftยณ: 1,000 รท 16.0185 โ 62.43 lb/gal: 1,000 รท 119.826 โ 8.35 Iron, at 7.87 g/cmยณ, is 7,870 รท 16.0185 โ 491 lb/ftยณ. Density also gives mass from volume: a 10 cm cube of iron (1,000 cmยณ) weighs 1,000 ร 7.87 = 7,870 g, about 7.9 kg.
Things to be aware of
- lb/gal uses the US gallon (about 3.785 L); imperial-gallon figures differ.
- The density of liquids and gases changes with temperature and pressure. Check the conditions behind any reference value.
- Specific gravity is a dimensionless ratio against water, numerically close to the g/cmยณ value.
- The bulk density of a powder includes the gaps between grains, so it is lower than the density of the material itself.
FAQ
What's the density of water?
Water's density is about 1 g/cmยณ (= 1000 kg/mยณ), a handy reference point for gauging other materials.
Are g/cmยณ and kg/L the same value?
Yes โ g/cmยณ and kg/L are numerically identical (both equal 1000 kg/mยณ).
Can this help check imported material density specs?
Yes โ you can convert lb/ftยณ or lb/gal specs from imported products into kg/mยณ or g/cmยณ for comparison.