Gas Properties Calculator — online
543 chemicals in one alphabetical list, or a mixture of up to 12: Z, density, cp with pressure correction, viscosity, conductivity, heating values and hazard data at any T and P.
Yellow cells are inputs; orange cells are choices; blue cells choose the unit. Select or hover over an input to see its help in the box below the toolbar. The sheet is the same as the Excel tool (USD 49) — the Guide, method and references are in the Excel file.
What this gas properties calculator does
Pick a gas or a mixture, enter T and P, and every property appears. 543 chemicals in one alphabetical list, or a mixture of up to 12: Z, density, cp with pressure correction, viscosity, conductivity, heating values and hazard data at any T and P.
- 543 chemicals, A to Z. Chosen for fertilizer, oil and gas and chemical plants, in one alphabetical list for every industry.
- Mixtures of up to 12. Presets for natural gas, air, flue gas and synthesis gases, or your own analysis in mole % or mass %.
- Full real-gas properties. Z, density, cp and cv with the pressure correction, γ, speed of sound, Joule–Thomson coefficient, viscosity and thermal conductivity.
- Heating values. HHV and LHV by mass and by volume, Wobbe index, stoichiometric air and flammability limits.
- Hazard data. NFPA 704 ratings, GHS statements, flash point and autoignition temperature.
- Every value traceable. Each value shows its source and a data class (A to D), so you know how far to trust it.
What you enter
- Calculate for
- Chemical
- Temperature
- Pressure (absolute or gauge – pick the unit)
- Table: start temperature
- Table: end temperature
What you get
- State at these conditions
- Vapour pressure at the temperature
- Boiling (saturation) temperature at the pressure
- Dew point at the pressure (ideal-solution estimate)
- Molar mass
- Compressibility factor Z
- Density
- Specific volume
- Density at normal conditions (0 °C, 1.01325 bar)
- Density at standard conditions (15 °C, 1.01325 bar)
- Relative density to air (ideal gas)
- Specific heat cp (real gas)
- Specific heat cv (real gas)
- Ideal-gas specific heat cp°
How it was checked
36 states against reference equations of state: Z within 0.1 % near 1 atm; heating values within 0.1 % of NIST.
Related
- Calculation guide — the equations behind this tool, with a worked example.
- Gas Properties Calculator Excel tool — USD 49, keep the workbook and its Guide.
- All 40 online tools
Questions
Is the gas properties calculator free?
You can enter and check all your data free. The full results, findings and printable sheet are unlocked with a 3-run pack (USD 9), a monthly subscription to all 40 online tools (USD 15) or a yearly one (USD 99).
Are the results the same as the Excel tool?
Yes. The online tool runs the formulas of the Gas Properties Calculator Excel workbook, checked cell by cell against the Excel file.
Which units can I use?
SI, US customary and British units — choose the unit next to each input.