Mass-radius diagram of exoplanets with mass and radius derived with precision better than 20% and 10%, respectively. The colour indicates the stellar insolation in Earth units (see colour bar in the upper left corner). The mass and radius of TOI-4602 b, as derived in this work, are highlighted on the diagram. Theoretical mass-radius curves, computed assuming a surface temperature of 1000 K, are over-plotted for reference. The curve corresponding to a 20% Fe core mass fraction is taken from Zeng et al. (2016), while the remaining composition models are from Zeng et al. (2019). From top to bottom, the curves correspond to: Earth-like rocky cores (32.5% Fe + 67.5% MgSiO₃) with a 0.3% and 1% H₂ envelopes, and rocky compositions with varying silicates fractions (100% Fe, 33% Fe + 66% MgSiO₃, 20% Fe + 80% MgSiO₃, 100% MgSiO₃). This plot has been generated with mr-plotter (Castro-González et al. 2023, https://github.com/castro-gzlz/mr-plotter/).