RPM vs RCF

RPM stands for "Revolutions per minute." This is how centrifuge manufacturers generally describe how fast the centrifuge is going. The rotor, regardless of its size, is revolving at that rate. The force applied to the contents varies by the size of the centrifuge rotor.

RCF (relative centrifugal force) is measured in force x gravity or g-force. This is the force exerted on the contents of the rotor, resulting from the revolutions of the rotor.

It is RCF, not RPM that separates aqueous solutions in the centrifuge. RPM can be calculated for any centrifuge by this equation:

RCF  =  1.1118 x 10^-5  x  r  x   rpm²
Where r is the rotor radius in centimeters