Unit Conversion

Convert numbers between two units quickly and precisely

Kinematic Viscosity

Unit Conversion

Convert kinematic viscosity: m²/s, stokes, and centistokes

Kinematic viscosity describes a fluid's flow behavior under gravity and is stated in square meters per second (m²/s), the SI unit. In engineering, stokes (St), centistokes (cSt), and, in the US, square feet per second (ft²/s) are also common.

Key conversion factors:

  • 1 stokes (St) = 10^-4 square meters per second
  • 1 centistoke (cSt) = 1 square millimeter per second – equal to the viscosity of water at 20 °C
  • 1 square foot per second (ft²/s) = 0.0929 square meters per second

Applications:

  • Lubricant technology: classifying engine and hydraulic oil in centistokes
  • Process engineering: flow behavior of process fluids
  • Food technology: viscosity of honey, syrup, and other viscous products

The kinematic viscosity converter supports comparing technical lubricant specs. For dynamic viscosity (independent of density), use the dynamic viscosity converter.

Frequently asked questions about converting kinematic viscosity

1 centistoke (cSt) equals 10^-6 m²/s, i.e. 1 square millimeter per second. That happens to also be roughly the kinematic viscosity of water at 20 °C, which makes cSt a practical reference unit.

Dynamic viscosity describes a fluid's pure resistance to flow (in Pa·s), while kinematic viscosity also accounts for density: kinematic viscosity = dynamic viscosity / density. It describes how a fluid behaves under the influence of gravity.

1 stokes (St) equals 10^-4 m²/s and is the classic CGS unit of kinematic viscosity. Since stokes would be an unwieldy large value for many real liquids, the hundredth of a stokes, i.e. centistokes (cSt), is usually used instead.