Enter the air pressure, water vapor pressure, and air temperature into the air density calculator. The calculator will display the current air density at those conditions.
Air Density Formula
The following formula is used to calculate air density.
ρ = (pd / (Rd * T)) + (pv / (Rv * T))
- pd is the pressure of dry air in Pa,
- pv is the water vapor pressure in Pa,
- T is the air temperature in Kelvins,
- Rd is the specific gas constant for dry air equal to 287.058 J/(kg·K), and
- Rv is the specific gas constant for water vapor equal to 461.495 J/(kg·K).
Air Density Definition
Air density is the density of air in any specific temperature and pressure.
How to calculate air density?
How to calculate air density
- First, determine the pressure of dry air
This can be calculated using a formula, or using a table for air pressure at certain temperatures.
- Next, determine the water vapor pressure
This is dependent on the relative humidity.
- Measure the air temperature
Measure the air temperature and convert it to Kelvin.
- Calculate the air density
Calculate the air density using the formula above.
Air density if the total mass of air within a given volume.
Air density can change with temperature and pressure. Increase pressure and temperature both increase density because they are forcing more air into a smaller volume.