Density Calculator
Density links mass and volume. Enter any two of the three and this works out the missing one, with the answer shown in the units scientists, engineers and shipping forms actually use.
| Solve for | |
| Mass | g |
| Volume | cm³ |
| Density | g/cm³ |
Result
Your result will appear here.
How it works
Density is mass per unit volume. Every substance has a characteristic density at a given temperature, which is why density identifies materials, predicts whether something floats, and converts between weight and volume for shipping, cooking and dosing.
Because the three quantities are tied together by one multiplication, knowing any two fixes the third. This page lets you solve in either direction rather than only the common mass-and-volume case.
Formula
The symbol ρ (rho) is used for density; the three forms below are the same equation rearranged.
- ρ = m ÷ V (density from mass and volume)
- m = ρ × V (mass from density and volume)
- V = m ÷ ρ (volume from mass and density)
- kg/m³ = g/cm³ × 1,000
- lb/ft³ = g/cm³ × 62.428
Worked example
500 g of material occupying 250 cm³: ρ = 500 ÷ 250 = 2 g/cm³, which is 2,000 kg/m³ and 124.9 lb/ft³. That is about the density of concrete or bottle glass, so the sample would sink quickly in water.
Assumptions
The material is assumed to be uniform, with no trapped air and no mixture of phases. A loose powder, a porous solid or a packed aggregate has a bulk density much lower than the density of the solid material itself. Temperature and pressure change density slightly for liquids and gases — noticeably for gases — so figures are only exact at the stated conditions.
Reading the result
Watch the units before you trust a comparison. Density in g/cm³ is numerically the same as specific gravity, which is why water reads 1.000; in kg/m³ the same material reads 1,000, and in lb/ft³ about 62.4. Anything with a density below 1 g/cm³ floats in water, though shape matters as much as density for a hollow object.
For general information only. Use measured values where precision matters.
How to use the Density Calculator
It takes a few seconds, and every figure is calculated in your browser.
- Choose what to solve for.
- Enter the mass.
- Enter the volume.
- Enter the density.
- Press Calculate — the result appears in the dark panel beside the form.
- Use Copy, CSV, Share or Print under the result if you want to keep it.
Density Calculator — frequently asked questions
What formula does the Density Calculator use?
The symbol ρ (rho) is used for density; the three forms below are the same equation rearranged. ρ = m ÷ V (density from mass and volume) m = ρ × V (mass from density and volume) V = m ÷ ρ (volume from mass and density) kg/m³ = g/cm³ × 1,000 lb/ft³ = g/cm³ × 62.428
How does the Density Calculator work?
Density is mass per unit volume. Every substance has a characteristic density at a given temperature, which is why density identifies materials, predicts whether something floats, and converts between weight and volume for shipping, cooking and dosing. Because the three quantities are tied together by one multiplication, knowing any two fixes the third. This page lets you solve in either direction rather than only the common mass-and-volume case.
What assumptions and limitations should I know about?
The material is assumed to be uniform, with no trapped air and no mixture of phases. A loose powder, a porous solid or a packed aggregate has a bulk density much lower than the density of the solid material itself. Temperature and pressure change density slightly for liquids and gases — noticeably for gases — so figures are only exact at the stated conditions.
Can you walk through a worked example?
500 g of material occupying 250 cm³: ρ = 500 ÷ 250 = 2 g/cm³, which is 2,000 kg/m³ and 124.9 lb/ft³. That is about the density of concrete or bottle glass, so the sample would sink quickly in water.
Last updated 10 November 2026 · Formula, worked example and assumptions are documented above, and every result is calculated in your browser.