Mass-radius diagram of well-characterised planets with R < 3 R_⊕ and M < 10 M_⊕. The plot shows the planets from the TEPcat catalogue (Southworth 2011, visited on 8 November 2021) with ΔM and ΔR < 30%. Planets withhost star temperatures T_eff < 4000 K are shown in orange, and planets with hotter hosts are shown in grey. GJ 3929 b is marked with a red diamond. Additionally, theoretical mass-radius relations from Zeng et al. (2019) are shown for reference.