A common quantity used to describe the collection efficiency of a froth flotation process is flotation recovery (). This quantity incorporates the probabilities of collision and attachment of particles to gas flotation bubbles.
where:
* , which is the product of the probability of the particle being collected () and the number of possible particle collisions ()
*  is particle diameter
*  is bubble diameter
*  is a specified height within the flotation which the recovery was calculated
*  is the particle concentration
The following are several additional mathematical methods often used to evaluate the effectiveness of froth flotation processes. These equations are more simple than the calculation for flotation recovery, as they are based solely on the amounts of inputs and outputs of the processes.
For the following equations:
*  is the weight percent of feed
*  is the weight percent concentrate
*  is the weight percent of tailings
* , , and  are the metallurgical assays of the concentrate, tailings, and feed, respectively
Ratio of feed weight to concentrate weight  (unitless)
Percent of metal recovered () in wt%
Percent of metal lost () in wt%
Percent of weight recovered  in wt%
This can be calculated using weights and assays, as . Or, since , the percent of metal recovered () can be calculated from assays alone using .
Percent of metal lost is the opposite of the percent of metal recovered, and represents the material lost to the tailings.