Formula & worked example
x=(h−hf)/(hg−hf); h=hf+x(hg−hf).
With hf=763 and hg=2778 kJ/kg, mixture enthalpy 2576.5 kJ/kg corresponds to 90% quality.
Heating & HVAC engineering calculator · Updated Sep 17, 2026
Steam Quality Calculator — Dryness Fraction, Enthalpy & Wet Steam
Calculate wet-steam quality from mixture enthalpy and saturated liquid/vapor enthalpies, or mixture enthalpy from entered dryness fraction.
Inputs
Live result
Calculated quality 0.9 (90%)
Reverse enthalpy at entered quality 2,576.5 kJ/kg
Mixture lies within the entered saturation enthalpy interval
Assumptions & limits
- Saturated liquid/vapor enthalpies must correspond to the same pressure or temperature.
- This lever-rule calculator does not replace a full IAPWS property solver.
Frequently asked questions
What does this Steam Quality Calculator calculate?
Calculate wet-steam quality from mixture enthalpy and saturated liquid/vapor enthalpies, or mixture enthalpy from entered dryness fraction.
What units are supported?
Inputs state their unit basis and results include practical SI and US customary equivalents where useful, so the calculation can be checked against field data and equipment schedules.
Can I use this for final equipment selection?
Use it for transparent first-pass sizing and engineering cross-checks. Final selections should use measured conditions, manufacturer performance data and applicable codes or design standards.