The present paper aims at providing simplified ways of estimating the main geometrical and dilution characteristics of inclined round negatively buoyant jets issuing in a calm homogeneous fluid. The trajectory of the upper boundary and the jet axis (centerline) are approximated in non-dimensional form by a 2nd degree polynomial (parabola), the coefficients of which are determined for specific discharge angles between 30° and 85° by fitting relevant experimental data. The estimates obtained seem to be in reasonable agreement with experimental results and model predictions. The length of the approximate trajectories is correlated with measured values of the ultimate dilution and the effect of the discharge angle on the dilution is discussed. Finally, the variation of the coefficients of the parabola with the angle is investigated, and a functional dependence is proposed.