We demonstrate a general single-pot heating method for preparing iron-doped zinc oxide nanocrystals from acetyl acetonate precursors in non-aqueous solvents. The particles were characterised by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), UV-visible (UV-Vis) and Fourier transform infrared (FTIR) optical absorbance spectroscopies. The dependences of the size of the nanocrystals and doping level on the synthesis temperature and precursor composition were elucidated and modelled.