We report the results of experiments using high-resolution imaging and digital analysis of transient frost growth to obtain quantitative information on frost thickness. The measurement technique provides faster data acquisition and much higher accuracy than traditional approaches. An empirical model of frost growth that captures the fast and slow growth periods is developed based on this data. The key physical and correlating parameter is the ratio of sensible heat transfer-to-total heat transfer, and the growth rate varies inversely with this ratio. The resulting correlation faithfully captures measured growth rates across a wide spectrum of frosting conditions and gives better predictive capability than that of existing correlations. The present model eliminates the need for specifics of the experimental apparatus and test surface as factors in prediction, as well as the necessity of measuring the frost–air interface temperature.