Density Calculator

Find density, mass, or volume from the other two, using density = mass ÷ volume.

⏱ Updated: 17 Sep 2026

Calculator

Free density calculator: find density, mass, or volume from the other two, using density = mass ÷ volume.

Use consistent units throughout (e.g. mass in grams and volume in mL/cm³ to get density in g/mL, or mass in kg and volume in m³ to get density in kg/m³).

Enter any two of density, mass, and volume to calculate the third.

How to Use the Density Calculator

Any two of density, mass, and volume — leave the one being solved for blank, and the calculator figures out which formula rearrangement to use from what's missing.

density = mass ÷ volume

Same relationship whether you're weighing a rock, a liquid, or a gas. This Density Calculator solves for whichever of the three you're missing — mass = density × volume, or volume = mass ÷ density, depending on what you've got.

Units matter more here than in most formulas, because "density" numerically means completely different things depending on what you measured in — g/mL, kg/m³, and lb/ft³ all describe the same physical property but land on wildly different numbers for the same substance. Mix grams with cubic meters and you get a number that isn't wrong exactly, just meaningless.

Floating and sinking come down entirely to this ratio: an object floats when it's less dense than the fluid around it, sinks when it's denser. A solid steel block sinks, but a steel ship floats — not because the steel changed, but because the ship's overall density, hollow hull and all, is lower than water's.