Temperature interpolation
mu = mu1 + (mu2 - mu1) x (T - T1) / (T2 - T1)
T in degrees C
Air property calculator
Dynamic Viscosity of Air Calculator
Calculate dynamic viscosity of dry air from temperature, with values reported in common engineering units.
Instant air viscosity solver
Enter air temperature
Results update automatically using interpolated dry-air values at 1 atm. Use Celsius, Fahrenheit, or Kelvin.
Calculated result
Formulas
Dynamic viscosity formulas and conversions
Common conversions
1 Pa.s = 1000 cP
1 Pa.s = 0.0208854 lb/(ft.s)
K = degrees C + 273.15
The calculator linearly interpolates tabulated dry-air dynamic viscosity values at standard atmospheric pressure. For high-temperature, high-pressure, or humid-air work, verify values against project-grade thermophysical data.
Reference table
Dynamic viscosity of air reference table
| Temperature (°C) | Dynamic viscosity, mu (Pa.s) |
|---|---|
| -20 | 1.458e-5 |
| -10 | 1.556e-5 |
| 0 | 1.656e-5 |
| 10 | 1.758e-5 |
| 15 | 1.804e-5 |
| 20 | 1.849e-5 |
| 25 | 1.894e-5 |
| 30 | 1.940e-5 |
| 40 | 2.032e-5 |
| 50 | 2.123e-5 |
| 60 | 2.214e-5 |
| 70 | 2.305e-5 |
| 80 | 2.395e-5 |
| 90 | 2.485e-5 |
| 100 | 2.574e-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
Dynamic viscosity
Dynamic viscosity measures a fluid's resistance to shear. For air, it affects pressure drop, boundary layers, Reynolds number, and convective heat transfer.
Temperature effect
Unlike most liquids, gas viscosity generally increases as temperature rises because molecular momentum exchange increases.
Design use
Use dynamic viscosity in duct flow, fan checks, aerodynamic drag, CFD setup, Reynolds number calculations, and heat-transfer estimates.
Assumption
This page assumes dry air at approximately 1 atm. Humidity and pressure can change detailed results.
FAQ
Dynamic viscosity of air questions
What is the dynamic viscosity of air at 15 degrees C?
At 15 °C and 1 atm, dry air dynamic viscosity is approximately 1.804 x 10-5 Pa.s.
Does air viscosity increase with temperature?
Yes. The dynamic viscosity of air increases gradually as temperature increases.
Is this calculator for humid air?
No. It is intended for dry air property checks at standard atmospheric pressure.
Related
Air property tables
Density of Air
Air density values for common engineering temperature and pressure lookups.
Kinematic Viscosity of Air
Kinematic viscosity values for air across practical engineering conditions.
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.