Science & engineering
Ideal gas density calculator
Calculate mass density from absolute pressure, temperature and molar mass.
A clear answer. Here’s how.
Rearranges PV=nRT and mass=n×molar mass to give ρ=PM/(RT). Converts kPa to Pa and g/mol to kg/mol, using R=8.31446261815324 J/(mol·K). Reports kg/m³, numerically equal g/L, and ideal molar volume. Pressure must be absolute. The model excludes real-gas compressibility, humidity and composition changes.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Absolute pressure (kPa)
- 101.325
- Absolute temperature (K)
- 273.15
- Molar mass (g/mol)
- 28.97
Example result
- Ideal mass density
- 1.29249751776 kg/m³
- Density in grams per litre
- 1.29249751776 g/L
- Ideal molar volume
- 22.413969545 L/mol