Intracellular macromolecular crowding impacts biomacromolecule behavior, including oligomerization, phase separation, and diffusion. However, understanding crowding effects in cells is challenging as cells respond and adapt to perturbations. Therefore, replicating in-cell crowding in liposomes would provide a good alternative to studying the consequences of macromolecular crowding. Here, we achieve physiological macromolecular crowding levels using