A modular mold system includes a hot half and a cold half. The hot half has a heated distributor assembly to receive molding material from an injection molding machine. The distributor assembly has a forward side that is opposite a side of the distributor assembly that faces the injection molding machine. A plurality of heated multi-nozzle units may also be provided. Each multi-nozzle unit has a manifold and a plurality of forward-extending nozzles. Each multi-nozzle unit is individually forwardly removably fastened to the forward side of the distributor assembly and removable from the distributor assembly while the distributor assembly is fastened to the first platen. The cold half includes a mounting plate and a plurality of cold-side units associated with the multi-nozzle units. Each cold-side unit is removably fastened to the mounting plate and engagable with one of the multi-nozzle units to define the one or more mold cavities.