How to use the absolute humidity calculator
Find the mass of water vapor per cubic metre of air from temperature and relative humidity. Enter air temperature, relative humidity in the fields above; the actual vapor pressure, absolute humidity are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “absolute humidity”, “grams of water per cubic metre”, “vapour density of air”, “calculate absolute humidity”, “find actual vapor pressure”.
Formula
Variables
- T — Air temperature (°C)
- RH — Relative humidity (%)
Worked example
With air temperature = 25 °C, relative humidity = 60 %, the calculator gives actual vapor pressure ≈ 19.00458 hPa; absolute humidity ≈ 13.81282 g/m³.
Frequently asked questions
What is the absolute humidity calculator used for?
Find the mass of water vapor per cubic metre of air from temperature and relative humidity. It helps with questions such as “absolute humidity”, “grams of water per cubic metre”, “vapour density of air”.
What is the formula for the absolute humidity calculation?
Actual vapor pressure (hPa) = 6.112 × exp(17.67 × T / (T+243.5)) × RH / 100. Absolute humidity (g/m³) = 216.7 × [Actual vapor pressure] / (T+273.15). Here T is air temperature (°C), RH is relative humidity (%).
What inputs do I need for the absolute humidity calculator?
You need air temperature in °C, relative humidity in %. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the absolute humidity calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the absolute humidity result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.