Dynamic viscosity
Viscosity is a fluid’s resistance to flow: honey has a high viscosity, water a low one. The SI unit is the pascal-second, but the centipoise is far more common because water at 20 °C has a viscosity of almost exactly 1 cP. One centipoise equals one millipascal-second.
| Fluid (about 20 °C) | Viscosity (cP) |
|---|---|
| Air | 0.018 |
| Water | 1.0 |
| Olive oil | about 80 |
| SAE 30 motor oil | about 200–300 |
| Honey | 2,000–10,000 |
Kinematic viscosity (stokes, centistokes, m²/s) is dynamic viscosity divided by density and needs the fluid’s density to convert.