About ChangeDetectionStrategy and components

I want to use ChangeDetectionStrategy.OnPush on my whole App, but I don’t know if I have to define this only in the page where I’ll use my custom components or if I also have to define it in the component itself aside of the page.

Is it needed to define the detectionstrategy on the page only? Or in both custom component and page where it’s used?

I think it’s just in the page but I wanna be sure.

Thanks.