Definition
nu = mu / rho
mu = dynamic viscosity
rho = density
Air property calculator
Kinematic Viscosity of Air Calculator
Calculate kinematic viscosity of dry air from temperature for Reynolds number, airflow, and heat-transfer checks.
Instant kinematic viscosity solver
Enter air temperature
Results update automatically using interpolated dry-air values at 1 atm. Use Celsius, Fahrenheit, or Kelvin.
Calculated result
Formulas
Kinematic viscosity formulas and conversions
Common conversions
1 m^2/s = 1,000,000 cSt
1 m^2/s = 10.7639 ft^2/s
K = degrees C + 273.15
The calculator linearly interpolates tabulated kinematic viscosity values for dry air at standard atmospheric pressure. Kinematic viscosity combines the effects of dynamic viscosity and density.
Reference table
Kinematic viscosity of air reference table
| Temperature (°C) | Kinematic viscosity, nu (m^2/s) |
|---|---|
| -20 | 1.10e-5 |
| -10 | 1.18e-5 |
| 0 | 1.27e-5 |
| 10 | 1.36e-5 |
| 15 | 1.41e-5 |
| 20 | 1.46e-5 |
| 25 | 1.48e-5 |
| 30 | 1.53e-5 |
| 40 | 1.62e-5 |
| 50 | 1.72e-5 |
| 60 | 1.81e-5 |
| 70 | 1.90e-5 |
| 80 | 1.99e-5 |
| 90 | 2.08e-5 |
| 100 | 2.16e-5 |
Guide
How to use this calculator
- Enter the air temperature.
- Select the temperature unit: °C, °F, or K.
- Use the interpolated dry-air result for early HVAC, airflow, heat-transfer, or fluid mechanics checks.
Reference
What the results mean
Kinematic viscosity
Kinematic viscosity is dynamic viscosity divided by density. It describes momentum diffusion in a flowing fluid.
Flow modeling
It is used directly in Reynolds number calculations, boundary-layer estimates, CFD inputs, and natural-convection checks.
Temperature effect
For dry air at 1 atm, kinematic viscosity generally increases with temperature because density falls as air warms.
Assumption
This page assumes dry air at approximately 1 atm. Use psychrometric data when humidity matters.
FAQ
Kinematic viscosity of air questions
What is the kinematic viscosity of air at 15 degrees C?
At 15 °C and 1 atm, dry air kinematic viscosity is approximately 1.41 x 10-5 m2/s.
How is kinematic viscosity different from dynamic viscosity?
Kinematic viscosity equals dynamic viscosity divided by density, so it includes both fluid resistance and density effects.
Why is kinematic viscosity useful?
It is commonly used in Reynolds number and flow-regime calculations.
Related
Air property tables
Density of Air
Air density values for common engineering temperature and pressure lookups.
Dynamic Viscosity of Air
Dynamic viscosity data for air used in fluid dynamics and heat transfer calculations.
Specific Heat of Air
Specific heat data for air used in thermodynamic and HVAC calculations.
Thermal Conductivity of Air
Thermal conductivity values for air used in heat transfer checks.