The expected chirp mass distribution of observed events for future gravitational wave detectors is extensively investigated in the presence of an exotic fluid component with an arbitrary equation of state, −1 !xpx=x<0, i. e., the so-called dark energy component. The results for a flat model dominated by dark energy are compared to those for the standard flat model dominated by cold dark matter. It is found that for a flat universe the chirp mass distribution shows a sensitive dependence on !x, which may provide an independent and robust constraint on the cosmic equation of state.