This study investigates the ring-opening multibranching polymerization (ROMBP) of glycidol using stochastic simulation. We analyzed the graph diameter of virtually generated macromolecules and examined how this parameter, denoted as dmathn, responds to variations in the initial composition of protected (monofunctional) and unprotected (bifunctional) monomers. The results uncover a distinct mathematical relationship between dmathn and the average degree of branching (DBₐᵥ). It was demonstrated that dmathn serves as a powerful indicator of the topological features of hyperbranched polymers obtained under different feed conditions. Unlike DBₐᵥ, dmathn more accurately reflects changes in macromolecular size. These findings establish dmathn as a reliable topological descriptor, offering new insights into the complex structure-property relationships of hyperbranched polymers.