Density of Air at Different Temperatures

The density of air is affected by several factors, mainly temperature, pressure, and humidity. At normal atmospheric conditions (20°C and 1 atmospheric pressure), the density of dry air is approximately 1.204 kg/m³.

The following charts and table provide comprehensive data on the density of dry air at different temperatures, taken under 1 atmospheric (atm) pressure. (1 atm = 101,325 Pa)

Click on the icon to switch between SI (kg/m³) and US customary/Imperial (lb/ft³) units.

Chart of air density at different temperatures in kilograms per cubic meter

Chart of air density at different temperatures in pounds per cubic feet

Air Density at Different Temperatures
Temperature °C	Density (kg/m³)
-25	1.422
-20	1.394
-15	1.367
-10	1.341
-5	1.316
0	1.292
5	1.268
10	1.246
15	1.225
20	1.204
25	1.184
30	1.164
35	1.146
40	1.127
50	1.093
60	1.060
80	1.000
100	0.9467
125	0.8868
150	0.8338
175	0.7868
200	0.7451
225	0.7078
300	0.6168
400	0.5238
500	0.4567
600	0.4043
700	0.3626
800	0.3289
900	0.3009
1000	0.2773

How to Calculate the Density of Air

To calculate the density of air, We need to calculate the partial pressure of the dry air and the partial pressure of the water vapor.

Step 1) We calculate the saturation vapor pressure (vapor pressure at 100% relative humidity).

There are several algorithims used for calculating the vapor pressure. In our calculator we use a polynomial developed by Herman Wobus, which gives a very reasonable precesion.

E_s = E_so / p⁸

Where:

E_s is the saturation pressure of water vapor (hPa)
e_so = 6.1078
p = c₀ + T (c₁ + T (c₂ + T (c₃ + T (c₄ + T (c₅ + T (c₆ + T (c₇ + T (c₈ + T (c9))))))))
T is the air temperature in degrees Celsius
c₀ = 0.99999683
c₁ = -0.90826951 × 10^-2
c₂ = 0.78736169 × 10^-4
c₃ = -0.61117958 × 10^-6
c₄ = 0.43884187 × 10^-8
c₅ = -0.29883885 × 10^-10
c₆ = 0.21874425 × 10^-12
c₇ = -0.17892321 × 10^-14
c₈ = 0.11112018 × 10^-16
c₉ = -0.30994571 × 10^-19

Step 2) Find the actual vapor pressure, by multiplying the saturation vapor pressure times the relative humidity:

p_v = E_s × Relative humidity

Step 3) Calculate the pressure of dry air p_d, by subtracting the vapor pressure from the total air pressure:

p_d = p_total - p_v

Step 4) Now, you can find the air density by plugin the values in the following equation:

$Density of humid air formula$

Where:

ρ_air is the density of air in kg/m³
p_d is the partial pressure of dry air in Pascals (Pa)
p_v is the pressure of water vapor in Pascals (Pa)
T is the temperature in Kelvins (K)
R_d is the specific gas constant for dry air = 287.058 J/(kg·K)
R_v is the specific gas constant for water vapour = 461.495 J/(kg·K)

Related Tables

References: 1) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017. 2) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 3) Wikipedia. “Density of air.”