[en] A detailed dynamical model of the globular cluster M3 is presented. The model is tidally limited and includes a realistic distribution of stellar masses. It is used to derive a total luminosity function for the cluster from the published luminosity function, and to give estimates of its total mass ([3.30 +- 0.15] x 10⁵ M/sub sun/) and M/L/subv/ ratio (1.6 +- 0.2 solar units). The model gives an excellent fit to the observed radial distribution of surface brightness and star counts over five decades in surface brightness: a good fit is not possible with the corresponding single-mass models