Purpose To describe a model for calculating induced stress on corneal incisions during intraocular lens implantation, and to compare the nozzles of common injectors using 2 incision sizes. Design Experimental study. Methods A finite element calculation model was developed and used to compare 7 commercially available injectors in widespread clinical use. The injectors' characteristics were measured and correlated for the stress they induced for 2.4- or 2.2-mm corneal incisions. Results Each injector created a different level of stress on the corneal incision. The stress was highest at the incision margins, and its level correlated with the injector's external circumference. The induced stress on 2.2-mm incision margins was about 9% higher compared to the induced stress on 2.4-mm incision margins. Conclusions A model for comparing stress induced on corneal incisions during intraocular lens implantation by 7 injectors revealed different levels of induced stress on the incision margins. It is therefore recommended that the choice of injector be matched to the size of the corneal incision.