Abstract. High-precision data on absolute dimensions of evolved eclipsing binaries have been used for a quantitative evaluation of the significance of convective overshoot in the stellar core. Eight detached double-lined eclipsing binaries with components close to or beyond the terminal age main sequence (TAMS) and masses between 2 and 12 M⊙ have been compared with evolutionary models using different overshooting parameters. The results are robust and indicate a systematic increase of the amount of convective overshoot with the stellar mass. Such determination constitutes a fundamental point for stellar structure and evolution theory.