Rational solutions of nonlinear evolution (NLE) equations have been the subject of numerous research papers. In this paper, a new generalized Kadomtsev–Petviashvili (KP) equation with diverse applications is investigated analytically. Multiple solitons, breather and rogue waves, and complexitons as special cases of rational solutions to the new generalized KP equation are formally extracted with the help of symbolic computations. Some two- and three-dimensional figures are considered to show the dynamics of rational solutions in the new generalized KP equation.