Mass to Volume Calculator (Volume to Mass by Density)

Convert mass to volume, or volume to mass, using density: pick water, oil, gasoline, metals or concrete, or enter your own density in any unit.

Calculator Functions

Function	What it does	What it requires
Volume from mass	Converts a mass to the volume it takes up, using the density of the material	Requires the mass, the material or a custom density, and the volume result unit
Mass from volume	Converts a volume to its mass, using the density of the material	Requires the volume, the material or a custom density, and the mass result unit
Density from mass and volume	Finds the density of something from its mass and its volume	Requires the mass, the volume and the density result unit

Mass goes in as kg, g, mg, lb or oz. Volume goes in as L, mL, cm³, m³, US fluid ounces, cups, pints, quarts or gallons, cubic inches or cubic feet. The material list holds nine typical densities, and Custom density accepts kg/m³, g/cm³, g/mL, kg/L, lb/ft³ or lb/in³. Every result also lists the mass in kg, the volume in L and the density in kg/m³ and g/mL.

Mass to Volume Formulas

V = m ÷ ρ [1]

V	Volume
m	Mass
ρ	Density of the material: its mass per unit of volume

Density is defined as mass divided by volume [1], so each function is that one relationship solved for a different quantity. Inputs are converted to kilograms and cubic meters first, using the standard unit factors [3].

Volume from mass

The mass is divided by the density. With water at 998.2 kg/m³, 500 g takes up 500 ÷ 0.9982 = 500.9 mL and 10 lb takes up 4.544 L, or 1.2 US gallons. The same 100 g is 100.18 mL of water, 108.7 mL of cooking oil and only 12.74 cm³ of steel. The material list uses these densities:

Material	Density (kg/m³)	Density (g/mL)	Volume of 1 kg
Water at 20 °C	998.2	0.9982	1.0018 L
Seawater	1,025	1.025	0.9756 L
Ethanol	789	0.789	1.2674 L
Cooking oil	920	0.92	1.087 L
Gasoline	740	0.74	1.3514 L
Oak wood	700	0.7	1.4286 L
Concrete	2,400	2.4	0.4167 L
Aluminum	2,700	2.7	0.3704 L
Steel	7,850	7.85	0.1274 L

Mass from volume

m = ρ × V

The volume is multiplied by the density. One liter of gasoline at 740 kg/m³ has a mass of 0.74 kg, 250 mL of ethanol is 197.25 g, and 1 US gallon of water at 20 °C is 3.779 kg, or 8.33 lb.

Density from mass and volume

ρ = m ÷ V

A sample of 95 g that fills 950 mL has a density of 95 ÷ 950 = 0.1 g/mL. A 78 g piece of metal with a volume of 10 cm³ has a density of 7.8 g/cm³, close to the steel value in the list.

How to Convert Mass to Volume

Mass and volume measure different things, so there is no fixed factor between them. The link is the density of the material. Look up or measure the density, put it in units that match the mass and the volume wanted, such as g/mL for grams and milliliters, and divide the mass by it. For water the answer in milliliters is almost the same number as the mass in grams, because water is close to 1 g/mL [2].

How to Convert Volume to Mass

Multiply the volume by the density, again with matching units. A volume in liters times a density in kg/L gives kilograms, and a volume in mL times g/mL gives grams: 2 L of seawater at 1.025 kg/L is 2.05 kg.

Limits of This Estimate

The densities in the material list are typical figures. Real values change with temperature, salinity, alloy, moisture and blend, so use a measured or published density when the result matters. These estimates are based on the best available data and estimations.
The water value is for about 20 °C. Water is densest near 4 °C and slightly lighter when warmer [2].
Fluid ounces measure volume and ounces measure mass. Cups, pints, quarts and gallons are US customary measures.

Sources

NASA Glenn Research Center, Gas Density: density defined as mass divided by volume
U.S. Geological Survey, Water Science School, Water Density: water at about 1 g/mL and how its density changes with temperature
NIST, Guide for the Use of the International System of Units (SP 811), Appendix B.8: factors for pounds, ounces, US liquid measures, cubic inches and cubic feet, and density units