Calculate dynamic viscosity, kinematic viscosity, density, and thermal properties of water at any temperature from 0–100 °C.
Water viscosity is one of the most frequently looked-up fluid properties in engineering. Dynamic viscosity μ drops dramatically with temperature — from about 1.79 mPa·s at 0°C to 0.28 mPa·s at 100°C — a six-fold decrease that profoundly affects flow behaviour, heat transfer, and pump performance.
This calculator uses the Vogel–Tammann–Fulcher correlation for dynamic viscosity and standard polynomial fits for density, thermal conductivity, specific heat, and surface tension. It outputs seven key properties: μ, ν, ρ, σ, c_p, k, and the Prandtl number. These are the essential inputs for Reynolds number, Nusselt number, and nearly every fluid-mechanics and heat-transfer correlation.
A visual bar chart shows how viscosity plummets with temperature, while the reference table gives values at 5°C intervals from 0°C to 100°C. Temperature presets include body temperature (37°C) for biomedical applications and other common engineering setpoints. That makes the page useful both as a lookup table and as a quick source for coupled fluid-property calculations at operating temperature.
Use this reference when you need temperature-dependent water properties for Reynolds number, pump sizing, pressure-drop estimates, or heat-transfer calculations without switching between multiple tables. It is especially useful when viscosity, density, and Prandtl number all need to stay synchronized at the same temperature in one calculation chain. That keeps the fluid-property inputs consistent when one operating temperature feeds several downstream calculations.
Dynamic viscosity: μ = A × 10^(B / (T − C)) A = 2.414×10⁻⁵, B = 247.8, C = 140 (T in Kelvin) Kinematic viscosity: ν = μ / ρ Prandtl number: Pr = μ c_p / k ρ, c_p, k, σ: standard polynomial correlations for 0–100°C
Result: μ = 1.002 mPa·s, ν = 1.004 × 10⁻⁶ m²/s
At 20°C (293.15 K), the VTF formula gives μ = 2.414e-5 × 10^(247.8/(293.15−140)) ≈ 1.002e-3 Pa·s. With ρ = 998.2 kg/m³, ν = 1.002e-3/998.2 = 1.004e-6 m²/s.
Water viscosity changes quickly with temperature, which means the same pipe, pump, or heat exchanger can behave very differently between cold-start and operating conditions. A design that looks acceptable at 20°C may produce very different pressure losses at 5°C or 80°C.
Dynamic viscosity is the quantity you need for shear-stress and constitutive relations, while kinematic viscosity is usually the value used in Reynolds number and many empirical flow correlations. If you are checking convective heat transfer, pair viscosity with thermal conductivity, specific heat, and Prandtl number rather than looking at viscosity in isolation.
These values are intended for liquid water near atmospheric pressure over the stated temperature range. They are not a substitute for steam tables, high-pressure property databases, or saline-water correlations.
In liquids, viscosity arises from intermolecular cohesive forces. Higher temperature gives molecules more kinetic energy to overcome these forces, reducing resistance to flow.
SI unit of dynamic viscosity is Pa·s. The CGS unit poise (P) = 0.1 Pa·s; centipoise (cP) = 1 mPa·s. Water at 20°C is almost exactly 1 cP, which historically defined the centipoise.
Dynamic viscosity μ (Pa·s) is the shear-stress-to-strain-rate ratio. Kinematic viscosity ν = μ/ρ (m²/s) divides out the density, representing the diffusion of momentum. ν appears in the Reynolds number.
At pressures below about 100 bar, the effect is negligible (< 2%). At very high pressures (e.g., deep ocean), viscosity increases measurably. This calculator assumes atmospheric pressure.
Pr = ν/α = μ c_p / k compares momentum diffusion to thermal diffusion. For water, Pr ranges from 13.4 at 0°C to 1.76 at 100°C. High Pr means the thermal boundary layer is thinner than the velocity boundary layer.
Seawater at 35 g/kg salinity is about 8% more viscous than freshwater at the same temperature. Apply a correction factor or use specific seawater property tables.