Density Converter
Enter a density value and its unit to see the equivalent in kg/m³, g/cm³, g/mL, lb/ft³, and lb/gal.
How density conversion works
Density is mass divided by volume. Grams per cubic centimeter (g/cm³) and grams per milliliter (g/mL) are numerically identical, since 1 cm³ equals exactly 1 mL — that's why water's density is both 1 g/cm³ and 1 g/mL.
Kilograms per cubic meter (kg/m³) is the SI unit; since 1 m³ = 1,000,000 cm³ and 1 kg = 1,000 g, 1 g/cm³ equals exactly 1,000 kg/m³. Pounds per cubic foot and pounds per US gallon are common in US engineering and industrial contexts.
Frequently asked questions
Why is water's density exactly 1 g/cm³?
The gram was originally defined as the mass of 1 cm³ of water at a specific temperature, so water's density works out to almost exactly 1 g/cm³ (it varies very slightly with temperature).
What's the difference between g/cm³ and g/mL?
They're exactly the same — a milliliter is defined as exactly 1 cubic centimeter, so these two density units are numerically identical.
How many kg/m³ is one g/cm³?
1 g/cm³ equals exactly 1,000 kg/m³.