Paraffin is a low-melting material that can be used as an environmentally friendly and high-energy fuel. It can also be considered as a promising material with phase transitions capable of accumulating heat. It is known that the period of induction of ignition of paraffin droplets consists of successive stages, the main ones of which are melting and evaporation. The paper examines the processes of evaporation of octadecane and docosane droplets in air at different temperatures. A method of studying the kinetics of evaporation of paraffin fuel droplets using digital photography of the research object and computer image processing has been developed. It is proved that the evaporation kinetics of the studied alkanes is described by the linear law of the change of the square of the diameter of the drop over time. Evaporation rate constants were found. There are no such data in the literature for these paraffins. The use of evaporation constants made it possible to find the time of complete evaporation of drops and to estimate the diffusion coefficient of paraffin vapor in air at different temperatures. As a result of the experiments, it was established that the rate of evaporation of octadecane is more than 4 times higher than the rate of evaporation of docosane. It was found that when the air temperature reaches the specified values, the rate of evaporation of the specified alkanes increases significantly.