A droplet growth model is formulated that describes the growth of homogeneous multi-component droplets suspended in a dilute gas–vapor mixture. The droplet is suspended in a real carrier gas, in which the vapors are diluted. The model is applicable for all Knudsen numbers. It is shown that the model can easily be extended to describe the growth of layered droplets. The model calculations are compared to the results of droplet growth experiments of supersaturated water and/or supersaturated n-nonane in methane. The model performs well for all the cases, except for the case when supersaturated n-nonane vapor is added to supersaturated water vapor in methane gas. In the latter case it is proposed that the discrepancies originate from the incomplete wetting of n-nonane on liquid water at the given conditions.