Kinematic Viscosity of Air Calculator

Compute ν (m²/s) from temperature, pressure, and RH

How to Use This Calculator

1

Enter Temperature

Provide air temperature in °C.

2

Enter Pressure

Provide station pressure in hPa.

3

Enter Relative Humidity

Provide RH as a percentage (0–100%).

4

Calculate

Review μ, ρ, and ν results.

Formula

μ = μ₀ · (T₀ + C)/(T + C) · (T/T₀)^1.5

ρ = p_d·100/(R_d·T) + e·100/(R_v·T)

ν = μ / ρ

Constants: μ₀=1.716×10⁻⁵ Pa·s at 0°C, C=111 K, R_d=287.058, R_v=461.495

About Kinematic Viscosity

Kinematic viscosity describes how easily air flows and diffuses, influencing Reynolds number and boundary layers in aerodynamics and HVAC design.

Frequently Asked Questions

How sensitive is ν to temperature?

Viscosity increases with temperature while density decreases, both raising ν.

Do I need to include humidity?

Humidity slightly reduces density; including RH gives a more accurate ν estimate.