viewpoint vs standpoint

viewpoint and standpoint both are nouns.

Word	Noun	Adjective	Verb	Adverb
viewpoint	Yes	No	No	No
standpoint	Yes	No	No	No

As nouns, viewpoint and standpoint are synonyms defined as:

viewpoint and standpoint: a mental position from which things are viewed

Other synonyms of viewpoint include point of view, stand.

viewpoint (noun)	standpoint (noun)
a mental position from which things are viewed	a mental position from which things are viewed
a place from which something can be viewed