The characterization of iron thin films grown at different substrate temperatures has been performed by x-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS). The film growing of iron at low temperatures provides an excellent system to test the results obtained from both techniques because the crystallographic grains present a variation of size and shape as a function of the growing temperature. In both cases, the shape of the particle must be taken into account to calculate their size. The comparison gives a very good agreement when appropriate models are used, showing the reasons for possible differences between the results obtained from a more simple XRD and EXAFS analysis applied to columnar growth systems. (C) 2004 American Institute of Physics.