Moist Air Enthalpy Calculator
Total energy content of moist air — the currency of coil and energy-recovery calculations.
Notice the 2501: every gram of moisture carries ~2.5 kJ of latent heat — at 18 g/kg, well over half the air's energy is in the water vapour.
Formula
Moist Air Enthalpy Calculator is a free air enthalpy for HVAC designers, technicians and energy auditors — 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 Moist Air Enthalpy Calculator
Total energy content of moist air — the currency of coil and energy-recovery calculations. The calculation implements h = 1.006·T + w·(2501 + 1.86·T) kJ/kg dry air (ASHRAE Fundamentals, ch. 1). Notice the 2501: every gram of moisture carries ~2.5 kJ of latent heat — at 18 g/kg, well over half the air's energy is in the water vapour.
How to use Moist Air Enthalpy Calculator
- 1Enter Dry-bulb temperature in °C.
- 2Enter Humidity ratio in g/kg.
- 3Read Specific enthalpy, US units instantly — no submit button needed.
Why use Moist Air Enthalpy Calculator?
- ✓Implements the standard formula — h = 1.006·T + w·(2501 + 1.86·T) kJ/kg dry air
- ✓Reference cited on-page: ASHRAE Fundamentals, ch. 1
- ✓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 Moist Air Enthalpy Calculator use?+
It computes h = 1.006·T + w·(2501 + 1.86·T) kJ/kg dry air, per ASHRAE Fundamentals, ch. 1. 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?+
Notice the 2501: every gram of moisture carries ~2.5 kJ of latent heat — at 18 g/kg, well over half the air's energy is in the water vapour.
Is this based on ASHRAE methods?+
The calculations follow the standard ASHRAE/ISHRAE formulations cited under the result, simplified where industry practice does the same. For permit-grade design, confirm with the full code procedure.
Is the Moist Air Enthalpy 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.
Related Engineering tools
Reynolds Number Calculator
Compute Re from density, velocity, pipe diameter and viscosity — with instant laminar/turbulent classification.
● LiveLaminar vs Turbulent Flow Classifier
Classify hydraulic-oil or process-fluid flow regime from kinematic viscosity, line velocity and tube bore.
● LiveBernoulli Equation Solver
Solve downstream pressure between two points from velocities, elevations and fluid density (ideal, lossless).
● Live