We study various methods for estimating the deconfinement temperature in nondynamical bottom-up AdS/QCD models in detail. We show that although there are many different possibilities to define the holographic parameters, certain reasonable theoretical and phenomenological restrictions on holographic models lead to realistic and rather stable predictions for the range of temperatures in the deconfinement crossover region at small baryon densities. In particular, we argue that the most successful approach is to take the scalar glueball trajectory from lattice simulations as a basic input in an improved version of the soft-wall holographic model.