Specific Volume Converter
Convert between specific volume units — cubic meter per kilogram, cubic centimeter per gram, liter per kilogram, liter per gram, cubic foot per pound, cubic inch per pound, cubic foot per ounce, and gallon (US) per pound.
Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.
Result
1 ft³/lb = 0.062359673 m³/kg
1 Cubic Foot per Pound = 0.062359673 Cubic Meters per Kilogram
1 Cubic Meter per Kilogram = 16.036005 Cubic Feet per Pound
1 ft³/lb in every supported unit
What is a Specific Volume Converter?
A specific volume converter translates the volume occupied by a unit of mass of a substance from one unit to another — for example, turning cubic feet per pound into cubic meters per kilogram, or liters per kilogram into gallons per pound. Specific volume is the exact reciprocal of density (v = 1/ρ): where density asks "how much mass is packed into this volume?", specific volume asks "how much space does this much mass take up?" It shows up constantly in thermodynamics and HVAC engineering, where steam tables, psychrometric charts, and refrigerant property tables are built around volume-per-unit-mass rather than mass-per-unit-volume.
Every unit below is defined relative to the cubic meter per kilogram, the SI derived unit of specific volume, so any conversion — metric to metric, imperial to imperial, or across systems — reduces to a single multiplication.
Conversion chart: Cubic Foot per Pound to Cubic Meters per Kilogram
Conversion table
| Cubic Foot per Pound (ft³/lb) | Cubic Meter per Kilogram (m³/kg) |
|---|---|
| 0.01 ft³/lb | 0.00062359673 m³/kg |
| 0.1 ft³/lb | 0.0062359673 m³/kg |
| 1 ft³/lb | 0.062359673 m³/kg |
| 2 ft³/lb | 0.12471935 m³/kg |
| 3 ft³/lb | 0.18707902 m³/kg |
| 5 ft³/lb | 0.31179836 m³/kg |
| 10 ft³/lb | 0.62359673 m³/kg |
| 20 ft³/lb | 1.2471935 m³/kg |
| 50 ft³/lb | 3.1179836 m³/kg |
| 100 ft³/lb | 6.2359673 m³/kg |
| 1000 ft³/lb | 62.359673 m³/kg |
Supported Units
| Unit | Symbol | In Cubic Meters per Kilogram |
|---|---|---|
| Cubic Meter per Kilogram | m³/kg | 1 m³/kg |
| Cubic Centimeter per Gram | cm³/g | 0.001 m³/kg |
| Liter per Kilogram | L/kg | 0.001 m³/kg |
| Liter per Gram | L/g | 1 m³/kg |
| Cubic Foot per Pound | ft³/lb | 0.062359673 m³/kg |
| Cubic Inch per Pound | in³/lb | 3.60783E-05 m³/kg |
| Cubic Foot per Ounce | ft³/oz | 0.99775476 m³/kg |
| Gallon (US) per Pound | gal/lb | 0.0083454042 m³/kg |
About These Parameters
- Value
- The number you want to convert, expressed in the "From" unit. Accepts decimals.
- From Unit
- The specific volume unit your input value is currently measured in.
- To Unit
- The specific volume unit you want the result converted into. Use the swap button to flip From and To instantly.
How Specific Volume Conversion Works
The Formula
Every unit here is defined by a fixed multiplier relative to the cubic meter per kilogram. To convert a value from one unit to another:
result = value × (factor of "From" unit ÷ factor of "To" unit)
For Cubic Foot per Pound → Cubic Meter per Kilogram: multiply by 0.062359673. For example, 1 ft³/lb × 0.062359673 = 0.062359673 m³/kg.
Specific Volume vs. Density: Reciprocal Quantities
Specific volume (v) and density (ρ) describe the same physical relationship — mass and the space it occupies — from opposite directions, and they are exact reciprocals of one another: v = 1/ρ. A substance with a high density, like steel at roughly 7,850 kg/m³, has a correspondingly tiny specific volume (about 0.000127 m³/kg), while a low-density substance like air at sea level has a much larger specific volume. Neither quantity is "more correct" than the other; engineers pick whichever one keeps a given calculation's numbers, formulas, and units cleanest, which is why both units families exist side by side across thermodynamics and fluid mechanics.
Where Specific Volume Matters: Thermodynamics and HVAC
Specific volume is the natural variable in steam tables and psychrometric (moist-air) charts, because thermodynamic cycles — compression, expansion, phase change — are usually analyzed per unit mass of working fluid rather than per unit volume. HVAC engineers use the specific volume of moist air to size ductwork and fans, refrigeration engineers use the specific volume of refrigerants to size compressors and evaporators, and power plant engineers use steam's specific volume (which swings enormously between liquid water and superheated steam) to size turbines and piping.
Example
1 ft³/lb equals 0.062359673 m³/kg. For scale, liquid water has a specific volume of about 0.001 m³/kg (roughly 0.016036005 ft³/lb) — it's very dense, so a kilogram of it takes up very little room — while dry air at sea level and room temperature has a specific volume of roughly 0.83 m³/kg (about 13.309884 ft³/lb), nearly a thousand times more space per kilogram.
Frequently Asked Questions
What's the difference between specific volume and density?
They are exact reciprocals: specific volume (m³/kg) tells you how much space a unit of mass takes up, while density (kg/m³) tells you how much mass fits into a unit of space. Multiplying a substance's specific volume by its density always gives exactly 1 — knowing either one lets you compute the other directly.
Why do engineers use specific volume instead of density?
In thermodynamic cycle analysis, quantities like work and heat transfer are naturally expressed per unit mass of working fluid, so equations written in terms of specific volume avoid extra division steps. Steam tables, refrigerant property charts, and psychrometric charts have historically been tabulated in specific volume for exactly this reason.
How accurate are these conversions?
Every conversion factor used here is derived from the exact, internationally recognized definitions of the underlying mass and volume units (the international pound, the US gallon, the liter) — results are limited only by floating-point display precision, not by rounded conversion constants.