So you just got a Glock or a Sig or a CZ or one of the many other pistols on the market and you want to attach an optic.
Is your slide already cut? Then pick a matching optic to the footprint. If you're shopping for a build you might as well get an optic cut. The cuts can be covered with a plate, plus according to the boy scouts, ‘be prepared’, or something like that. Or you have your trusty old EDC that you want to modernize, chances are your slide can be cut for a red dot optic.
In the year 2022/2023 there are a lot of optic choices and there are almost as many different footprints as there are optics, but many share the same footprint as you can see in the graphic below
If you haven’t already chosen your optic, maybe think about what footprint will have the most versatility for changes or upgrades down the line.
This is good information currently, but with new developments in optic cuts things can change at any time.