We present a rapid and flexible framework for the accurate calculation of the detection efficiency of fluorescence emission in isotropic media as well as in the vicinity of dielectric or metallic interfaces. The framework accounts for the dipole characteristics of the emitted fluorescence and yields the absolute detection efficiency by taking into account the total power radiated by the fluorophore. This analysis proved to be useful for quantitative measurements, i.e. the fluorescence detection at a glass–water interface for total internal reflection fluorescence microscopy in an epi- and a trans-illumination configuration.