Ideal Gas Density Calculator
Gas density at any pressure and temperature from molar mass via the ideal-gas law.
Good to ~1% for air and fuel gases below ~10 bar. CO₂ is 1.5× denser than air — why it pools in pits and tanks.
Formula
Ideal Gas Density Calculator is a free gas density for process, mechanical and water engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Ideal Gas Density Calculator
Gas density at any pressure and temperature from molar mass via the ideal-gas law. The calculation implements ρ = P·M / (R·T) (Çengel, Thermodynamics — ideal gas relations). Good to ~1% for air and fuel gases below ~10 bar. CO₂ is 1.5× denser than air — why it pools in pits and tanks.
How to use Ideal Gas Density Calculator
- 1Enter Molar mass in g/mol (Air 28.97 · CH₄ 16.04 · CO₂ 44.01 · H₂ 2.016).
- 2Enter Absolute pressure in kPa(a).
- 3Enter Temperature in °C.
- 4Read Density instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Ideal Gas Density Calculator?
- ✓Implements the standard formula — ρ = P·M / (R·T)
- ✓Reference cited on-page: Çengel, Thermodynamics — ideal gas relations
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Ideal Gas Density Calculator use?+
It computes ρ = P·M / (R·T), per Çengel, Thermodynamics — ideal gas relations. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Good to ~1% for air and fuel gases below ~10 bar. CO₂ is 1.5× denser than air — why it pools in pits and tanks.
Does this work for any fluid?+
Yes — density and viscosity are inputs (with common fluids suggested in the field hints), so the same physics applies to water, oils, gases and process fluids. Compute always runs in SI internally, so unit mix-ups can't corrupt the result.
Is the Ideal Gas Density Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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