Technical Calculator

Air Density Calculator

Enter the atmospheric pressure, temperature and relative humidity in the air density calculator and measure the air density of dry and moist air.

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The air density calculator instantly calculates the density of air in kg m3 at a certain temperature and pressure. Not only this, but the tool also calculates the dew point, air pressure, and water vapor pressure when the air is fully compressed.

How Does This Air Density Calculator Work?

Here’s how you can use our density of air calculator:

Input:

  • Enter the air pressure
  • Select the air temperature
  • Choose the Air type
  • Enter Relative humidity of air
  • Hit the calculate button to find the air density

Output: This density air calculator estimates the following calculations:

  • Air density
  • Dew point of air
  • Pressure of the dry air
  • Water vapor pressure

What Is the Density of Air Equation?

You can calculate the air density using the following equation:

ρ = [(Pd / (Rd * T)) + (Pv / (Rv * T))]

Where:

  • Pd = Pressure of dry air
  • Pv = Water vapor pressure
  • T = Temperature in Kelvins
  • Rd = Specific gas constant for dry air [287.058 J/(kg·K)]
  • Rv = Specific gas constant for water [461.495 J/(kg·K)]

If we set the temperature at 15 °C & pressure at 1013.25 hPa, the air density will be 1.225 kg/(m^3). At sea level, the atmospheric pressure is maximized due to high air pressure. Hence the air is denser at sea level and we can figure this out by the air density calculator. The density of the air is denoted by the Greek letter Rho (ρ) and it is the measure of the mass per unit volume and this is why we represent the density of air in kg m3 or g/m3.

How To Calculate Air Density?

If you are thinking about how to calculate density of air, then you need some basic weather parameters like pressure and temperature.

Air Pressure:

Air pressure is a force exerted on a surface by the air above it as gravity pulls it to Earth. The air pressure is commonly measured with a barometer or in Pascals. Air pressure:

The standard SI unit of pressure is Pascal and the other units are expressed as follows:

  • Pascals (Pa)
  • Standard Atmospheres (ATM)
  • Tor (Torr)
  • bar (bar)
  • Pounds per Square Inch (psi or lb/in2)
  • Technical Atmosphere (at or kgf/cm2)
  • Barad (Ba)
  • Pièze (ps)

Air Temperature:

The basic units of temperature are Kelvin (K), centigrade or Celsius (C), and Fahrenheit (F). You need to convert the Fahrenheit to Celsius and Kelvin to calculate air density. Air Temperature:

Dew Point:

The dew point is the temperature at which the water vapor starts to condense. You can compute the dew point manually or our air density calculator is able to use one of these values to compute the other.

Density of Air Lb/Ft3 of Pressure:

Here, you can find the density of air in lb/ft3.

Density of air Pressure Density of air lb/ft3
Density of air at 15 C 1 Pascal 0.00000075474
Density of air at 20 C 1 Pascal 0.00000074187
Density of air at 22 C 1 Pascal 0.00000073684
Density of air at 25 C 1 Pascal 0.00000072943
Density of air at 40 C 1 Pascal 0.00000069449

We can calculate the air-density in various units like [lbm/ft3], [sl/ft3*10-3] , [lbm/gal(US liq)], [kg/m3]. Now if you think about how to calculate the density of air in the above-mentioned units then the following table can be of great help. In this table, we have distinguished the specific weight and thermal expansion coefficient at various temperatures.

Temperature Pressure Specific weight Thermal expansion coefficient
[°F] [lbm/ft3] [sl/ft3*10-3] [lbm/gal(US liq)] [kg/m3] [lbf/ft3] [N/m3] [x10-3 °F-1]
-100 0.1104 3.431 0.01476 1.768 0.1104 17.34 2.83
-50 0.0968 3.010 0.01295 1.551 0.0968 15.21 2.48
-20 0.0902 2.803 0.01206 1.445 0.0902 14.17 2.30
0 0.0862 2.681 0.01153 1.382 0.0862 13.55 2.20
10 0.0844 2.624 0.01128 1.352 0.0844 13.26 2.15
20 0.0826 2.569 0.01105 1.324 0.0826 12.98 2.10
30 0.0810 2.516 0.01082 1.297 0.0810 12.72 2.06
40 0.0793 2.466 0.01061 1.271 0.0793 12.46 2.02
50 0.0778 2.418 0.01040 1.246 0.0778 12.22 1.98
60 0.0763 2.372 0.01020 1.222 0.0763 11.99 1.94
70 0.0749 2.327 0.01001 1.199 0.0749 11.76 1.90
80 0.0735 2.284 0.00982 1.177 0.0735 11.55 1.87
100 0.0709 2.203 0.00948 1.135 0.0709 11.14 1.80
120 0.0685 2.128 0.00915 1.097 0.0685 10.75 1.74
140 0.0662 2.057 0.00885 1.060 0.0662 10.40 1.68
160 0.0641 1.991 0.00856 1.026 0.0641 10.06 1.63
180 0.0621 1.929 0.00830 0.994 0.0621 9.75 1.58
200 0.0602 1.870 0.00804 0.964 0.060 9.45 1.53
250 0.0559 1.738 0.00747 0.896 0.0559 8.78 1.41
300 0.0522 1.622 0.00698 0.836 0.0522 8.20 1.30
400 0.0461 1.432 0.00616 0.738 0.0461 7.24 1.16
500 0.0410 1.274 0.00548 0.656 0.0410 6.43 1.05
700 0.0340 1.057 0.00455 0.545 0.0340 5.35 0.88
1000 0.0272 0.845 0.00363 0.4354 0.0272 4.27 0.70
1400 0.0213 0.663 0.00285 0.3416 0.0213 3.35 0.54
1800 0.0176 0.546 0.00235 0.2813 0.0176 2.76 0.45
2000 0.0161 0.501 0.00216 0.2583 0.0161 2.53 0.42

FAQs:

How To Find Air Density of Average Sea Level?

The average value of density of air at sea level is 1.29 grams/liter or 0.07967 pounds/cubic foot at 0 degrees and 32 degrees Fahrenheit at the average sea level. The barometric pressure is 29.92 inches of Hg or 760 mmHg.

What Is The Density of Air At 25 Celsius?

The Density of air at 25 degrees Celsius in kg/m3 is 1.168 kg/m3 at (25 °C and 100 kPa). The air density online calculator can find the density of air for both dry and moist atmospheres.

References:

From the source Wikipedia: Density of air, Temperature From the source iflycoast.com: Understanding Air Density, Effects of lower density on humans