Fe-Co alloys attracting interest due to their high magnetic induction and Curie temperature, were synthesized by an eco friendly electroless deposition with carbohydrates as reducing agents. It was shown that Fe1-xCox-С composite coatings retain high induction, while demonstrating an unusual behavior of magnetization at low temperatures. It was found that for each coating measured at different temperatures, there is a correlation between the local magnetic anisotropy constant K at a given temperature and the correlation radius of the local easy magnetization axis Rc. The functional type of this correlation is typical for nanoparticles or nanogranules in a composite, which made it possible to estimate the volume and surface magnetic anisotropy constants of metal granules of Fe-Co-C coatings.