oft vs frequently

oft and frequently both are adverbs.

Word	Noun	Adjective	Verb	Adverb
oft	No	No	No	Yes
frequently	No	No	No	Yes

As adverbs, oft and frequently are synonyms defined as:

Other synonyms of oft include often, oftentimes, ofttimes.

oft (adverb)	frequently (adverb)
many times at short intervals	many times at short intervals