This work aims to shape the productive behaviour of pastures, specifically Brachiaria brizantha cv. Toledo under nitrogen fertilisation using algorithms in the programming environment of the R software, in order to estimate the production of dry matter at different cut-off ages. For this, the logistics model was considered as a non-linear model. The usefulness of the R software in building confidence bands on the adjustment of non-linear models was demonstrated, specifically the logistical one for estimating dry matter production in grassland under nitrogenous fertilisation conditions at different cut-off ages. The logistical model showed a high precision to explain the kg MS· ha-1 of B. brizantha cv. Toledo accumulated depending on the cut-off age and nitrogen fertilisation levels, as well as the presence of a possible turning point, which was located in the rainy season around day 100 and the dry season around day 40, associated with the transition from one era to another. Finally, the results suggest that the forage species B. brizantha is influenced by the fertilisation dose, cut age, time of year and soil and climatic conditions.