Are you both starting the project at the same time? If so, 50/50 is fair, neither of you has added any value up to this point. If you've already built out the

Are you both starting the project at the same time? If so, 50/50 is fair, neither of you has added any value up to this point. If you've already built out the product and are just now bringing in a non-technical person you can possibly negotiate a better percentage for yourself. Even better if you've already brought in some revenue.