The emulsification process is primarily determined by the rate of fragmentation and coalescence of emulsion drops. However, there is presently no fast, reliable method for measuring these rates for pilot and production scale high pressure homogenizers. In this paper a method for simultaneous estimating fragmentation and coalescence is developed and tested based on the work of Hounslow and Ni (2004). Kernel type as well as rate extraction is performed based on the development of the total number of drops when recirculation an emulsion through a high-pressure homogenizer. The method has many advantages such as not requiring any specialty chemicals or complex analytical equipment. All measurements are made using laser diffraction equipment that is already standard for analyzing the effect of homogenization. Experiments show fragmentation and coalescence rates close to that seen in previous studies and the scaling of coalescence rate and fragmentation with homogenizing pressure is in accordance with theory. (c) 2012 Elsevier Ltd. All rights reserved.