Viscosity Calculator

Calculate dynamic and kinematic viscosity with real-time visualization

Fluid Properties

Enter fluid properties or select from common fluids

Pa·s
Please enter a valid positive number
Water: 0.001 Pa·s, Honey: ~10 Pa·s
kg/m³
Please enter a valid positive number
Water: 1000 kg/m³, Air: 1.2 kg/m³
°C
Viscosity changes with temperature
Flow Parameters (for Reynolds Number)

Enter flow characteristics for Reynolds number calculation

m/s
Please enter a valid positive number
m
Please enter a valid positive number
Pipe diameter or hydraulic diameter
Dynamic Viscosity
0.001
Pascal-seconds (Pa·s)
Kinematic Viscosity
0.000001
m²/s
Reynolds Number
100,000
Dimensionless
Viscosity Index
100
Measure of temperature sensitivity
Viscosity Comparison
Current Fluid
0.001 Pa·s
Air
0.000018 Pa·s
Water
0.001 Pa·s
Engine Oil
0.29 Pa·s
Honey
10 Pa·s

Common Fluid Viscosities

Fluid Dynamic Viscosity Kinematic Viscosity
Air (20°C) 0.000018 Pa·s 1.5 × 10⁻⁵ m²/s
Water (20°C) 0.001 Pa·s 1.0 × 10⁻⁶ m²/s
Blood (37°C) 0.003 Pa·s 2.8 × 10⁻⁶ m²/s
Engine Oil (SAE 30) 0.29 Pa·s 3.2 × 10⁻⁴ m²/s
Honey (20°C) 10 Pa·s 7.1 × 10⁻³ m²/s
Ketchup 50 Pa·s 5.0 × 10⁻² m²/s
Peanut Butter 250 Pa·s 0.25 m²/s

Understanding Viscosity

1

What is Viscosity? Viscosity is a measure of a fluid's resistance to flow. It describes the internal friction of a moving fluid.

2

Dynamic Viscosity (μ): Also known as absolute viscosity, measures the resistance to flow under an applied force. Units: Pa·s or poise (P).

3

Kinematic Viscosity (ν): Dynamic viscosity divided by fluid density (ν = μ/ρ). Units: m²/s or stokes (St).

Temperature Dependence: Viscosity decreases with increasing temperature for liquids and increases for gases.

Key Formulas

Dynamic Viscosity (μ) = Shear Stress / Shear Rate

Kinematic Viscosity (ν) = μ / ρ

Reynolds Number (Re) = (ρ × v × D) / μ

Where:
ρ = Fluid density
v = Flow velocity
D = Characteristic length
Viscosity Measurement Methods
Method Principle Applications
Capillary Viscometer Measures flow through a capillary tube Liquids, Newtonian fluids
Rotational Viscometer Measures torque on rotating spindle Non-Newtonian fluids, paints
Falling Sphere Measures terminal velocity of sphere Transparent fluids
Vibrating Viscometer Measures damping of vibrating element High-temperature fluids
Oscillating Viscometer Measures damping of oscillating surface Small sample volumes