unstained vs untainted

unstained and untainted both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unstained	No	Yes	No	No
untainted	No	Yes	No	No

As adjectives, unstained and untainted are synonyms defined as:

Other synonyms of unstained include stainless, unsullied, untarnished.

unstained (adjective)	untainted (adjective)
not stained	(of reputation) free from blemishes
without soil or spot or stain
(of reputation) free from blemishes
not having a coating of stain or varnish