The nucleation behavior of n-alkane droplets with carbon numbers ranging from 14 to 17 was observed in an electrodynamic balance. Changes in the elastic light-scattering pattern of the single levitated microdroplets indicate the phase transition from liquid to solid. Cooling/heating experiments showed larger supercooling temperatures than expected for alkane droplets with an alkane/air interface. Measurements of the nucleation rates Of C15H32 and C17H36 gave additional information about the dynamics of the nucleation process and allowed us to distinguish homogeneous from heterogeneous nucleation.