Parsec

CMD: provides interpolated isochrones for any age and metallicity, as well as luminosity functions, integrated magnitudes, etc. The photometry can be produced for many different broad- and intermediate-band systems, including non-standard ones.
TRILEGAL: a simulator of photometry for any galaxy field. The photometry can be produced for many different broad- and intermediate-band systems, including non-standard ones.
PARAM: Bayesian estimation of stellar parameters. Provides the most likely values of stellar mass, age, radius, surface gravity, etc., for a star of know photometry and distance (parallax).
AESOPUS: Low-temperature Rosseland mean opacities on demand.
YBC: tools to convert theoretical data into the photometry in many photometric systems. Tables of BC and variable extinction coefficients included. Obsolete link to the repository here. Cooming soon: inclusion of rotation effects!
COLIBRI: a stellar evolution code for the Asymptotic Giant Branch.