Standpoint and viewpoint are often synonymous with perspective, while point of view is often treated as gentle synonym of opinion. Incidentally, there is no reason to hyphenate point of view.

A standpoint is a person’s unique perspective or position on a particular issue or topic. It is shaped by a person’s experiences, beliefs, and values. A viewpoint, on the other hand, is a more general term that refers to a person’s opinion or attitude about something.

Standpoint may have connotations which tend to distinguish it from point of view and viewpoint; it is more often restricted to the mental point of view <consider totalitarianism from the German standpoint > and it more often connotes than definitely implies a fixed way of looking justified by one’s fundamental principles or one’s stock of information and not necessarily resulting in a limited understanding.