Water Viscosity Calculator

Calculate dynamic and kinematic viscosity of water at any temperature

Calculate Water Viscosity

Temperature range: 0-100°C for accurate results

Water Viscosity Results

Dynamic Viscosity (η)

mPa·s (Millipascal-seconds)1.2449
cP (Centipoise)1.2449
P (Poise)0.012449

Kinematic Viscosity (ν)

mm²/s1.2470
cSt (Centistokes)1.2470
St (Stokes)0.012470

Temperature: 20.0°C

Water Density: 0.9983 g/cm³

Formula: ν = η/ρ (Kinematic = Dynamic ÷ Density)

Temperature Analysis

Room temperature water has moderate viscosity, ideal for most applications.

Example Calculation

Room Temperature Water

Temperature: 20°C (68°F)

Dynamic Viscosity: 1.0016 mPa·s

Kinematic Viscosity: 1.0034 mm²/s

Water Density: 0.9982 g/cm³

Calculation Steps

1. Dynamic viscosity calculated using polynomial approximation

2. Water density calculated from temperature

3. Kinematic viscosity = Dynamic viscosity ÷ Density

4. ν = 1.0016 mPa·s ÷ 0.9982 g/cm³ = 1.0034 mm²/s

Types of Viscosity

η

Dynamic Viscosity

Resistance to flow under applied force

Units: mPa·s, cP, Poise

ν

Kinematic Viscosity

Flow speed under constant force

Units: mm²/s, cSt, Stokes

Reference Values

0°C (Ice point)1.787 mPa·s
20°C (Room temp)1.002 mPa·s
40°C (Body temp)0.653 mPa·s
60°C (Hot water)0.467 mPa·s
80°C (Near boiling)0.354 mPa·s
100°C (Boiling)0.282 mPa·s

Viscosity Tips

Higher temperature = lower viscosity

1 mPa·s = 1 cP (centipoise)

1 mm²/s = 1 cSt (centistoke)

Kinematic = Dynamic ÷ Density

Understanding Water Viscosity

What is Viscosity?

Viscosity is a fluid's resistance to flow or deformation. Think of honey versus water - honey has high viscosity (flows slowly), while water has low viscosity (flows easily). Temperature significantly affects viscosity, especially in liquids.

Why Does Temperature Matter?

  • Higher temperature increases molecular motion
  • Faster molecules overcome intermolecular forces easier
  • Result: Lower viscosity at higher temperatures
  • Critical for engineering and scientific applications

Dynamic vs Kinematic Viscosity

Dynamic Viscosity (η)

Measures the force needed to move fluid at a certain velocity

Formula: τ = η × (dv/dy)

Kinematic Viscosity (ν)

Measures how fast fluid flows under its own weight

Formula: ν = η/ρ

Key Insight: Dynamic viscosity depends on intermolecular forces, while kinematic viscosity also accounts for fluid density.

Units Explained

Dynamic Viscosity

• mPa·s (millipascal-seconds)
• cP (centipoise) = mPa·s
• P (poise) = 100 mPa·s

Kinematic Viscosity

• mm²/s (square millimeters per second)
• cSt (centistokes) = mm²/s
• St (stokes) = 100 mm²/s

Applications

  • 🔧Engineering: Pump design, pipeline flow calculations
  • 🧪Research: Fluid mechanics studies, material testing
  • 🏭Industry: Process design, quality control
  • 🌡️HVAC: Heat exchanger design, cooling systems