How to Convert From Centistoke to Centipoise

By Jonathan Marker
Viscosity is a measure of a substance's resistance to flow; in this image, the medium viscosity of water is illustrated.

Centistokes, denoted as cSt, is a unit of measure for kinematic viscosity, which is the ratio of dynamic or absolute viscosity to density. cSt is equivalent to the unit millimeters squared per second, the ratio of a liquid's density to its absolute viscosity in centipoises, denoted as cP. Centipoise is a unit of measure for absolute viscosity equivalent to one-hundredth of a poise, denoted by P. In the metric system, or SI, one poise is equivalent to one-tenth Pascal-second.

A Simple Conversion

First, to convert from centistokes to centipoise, you will use the formula cP = cSt*(Specific Gravity). Note: The specific gravity is the ratio of the density of one substance to the density of a reference substance, and because the common unit of measurement cancels out, specific gravity is given as a dimensionless number. We will use the specific gravity of water for this example, which at 20 degrees Celsius is 1.

Plug-In Values

Next, plug-in the value for cSt and multiply that value by the specific gravity. The kinematic viscosity of water is 1.0 millimeters-squared per second

Check Your Answer

Finally, check over your arithmetic and verify that your final value is 1 cP.

About the Author

Jonathan Marker is an aerospace analyst and graduate of Embry Riddle Aeronautical University. A current MA candidate in military studies at American Military University, he has written hundreds of articles on a wide range of general science, aviation and history topics. Marker is currently working on several science fiction projects.