A pound of feathers and a pound of lead weigh the same but fill wildly different boxes — specific volume is that box size per unit mass. It is simply volume divided by mass, v = V / m, the reciprocal of density. Steam engineers live by it: a kilogram of water occupies a liter as liquid but balloons to over 1,600 liters as steam at atmospheric pressure, and every turbine calculation starts from that expansion.

This calculator does the division. Type the total volume in cubic meters into the Volume (V, m³) box and the mass in kilograms into the Mass (m, kg) box; the Specific Volume (v, m³/kg) box returns the answer. A refrigeration tech in Texas charging a system, for instance, looks up the refrigerant's specific volume at the operating pressure, multiplies by the charge weight here in reverse, and knows exactly how much vapor the compressor will swallow per stroke. Scuba shops use the same ratio to state how many cubic feet of air a tank holds per pound of tank weight — the number that decides how long a dive lasts.

With the pre-filled defaults — Volume (V, m³) 2, Mass (m, kg) 5 — the Specific Volume Calculator returns Specific Volume (v, m³/kg) 0.4000. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.