Designed ankyrin repeat proteins (DARPins) are characterized by their remarkably small and compact molecular size compared to traditional monoclonal antibodies. A typical monomeric DARPin molecule possesses a molecular weight ranging between 14 and 18 kilodaltons (or 14,000 to 18,000 Daltons), which is roughly one-tenth the size of a standard human immunoglobulin G antibody. Even when multiple DARPin modules are genetically linked together to form multi-specific or biprotein constructs to engage multiple targets simultaneously, their overall molecular weight remains relatively low, facilitating rapid tissue penetration and efficient clearance profiles.