viewpoint vs point of view

viewpoint and point of view both are nouns.

Word	Noun	Adjective	Verb	Adverb
viewpoint	Yes	No	No	No
point of view	Yes	No	No	No

As nouns, viewpoint and point of view are synonyms defined as:

viewpoint and point of view: a mental position from which things are viewed

Other synonyms of viewpoint include stand, standpoint.

viewpoint (noun)	point of view (noun)
a mental position from which things are viewed	the spatial property of the position from which something is observed
a place from which something can be viewed	a mental position from which things are viewed