Dew Point Calculator

Calculate dew point temperature, vapor pressure, absolute humidity, and condensation risk from temperature, relative humidity, and pressure.

Input
Dew Point
Dew point temperature
T_d — Magnus inversion
9.515°C
Dew point depression
12.48°C
Low condensation risk
Vapor Pressure
Saturation vapor pressure
e_s(T)
2637.4Pa
Actual vapor pressure
e = RH × e_s
1186.8Pa
Moisture Content
Absolute humidity
ρ_w = e / (R_w · T)
8.713g/m³
Mixing ratio
w = 0.622 · e / (P − e)
7.372g/kg
Specific humidity
q = w / (1 + w)
7.318g/kg
Volume mixing ratio
e/P × 10⁶
11713.2ppmv
Abridged Optics — Dew Point Calculator v1.0Magnus–Tetens (Sonntag 1990): a = 611.2 Pa, b = 17.62, c = 243.12°C · R_w = 461.5 J/(kg·K) · M_w/M_a = 0.62198

All information, equations, and calculations have been compiled and verified to the best of our ability. For mission-critical applications, we recommend independent verification of all values. If you find an error, please let us know.