DOG FACT : In all dog breeds, eye sizes are the same.
The eye is the first major organ to develop in a foetus.
All the variations you see in dogs, size, color, temperament take place on the genetic level after the eyeball has developed. That’s why small dogs often seem to have bulging eyes. Their skulls are holding the same size orbs as their gigantic brethren.
The vets allow that there could be minor differences in eye size, and that disease, or bad genetics could result in an eye larger or smaller than usual, but, all things being equal, all dogs have the same size eyeballs.