in brief vs in short

in brief and in short both are adverbs.

Word	Noun	Adjective	Verb	Adverb
in brief	No	No	No	Yes
in short	No	No	No	Yes

As adverbs, in brief and in short are synonyms defined as:

Other synonyms of in brief include briefly, concisely, shortly.

in brief (adverb)	in short (adverb)
in a concise manner; in a few words	in a concise manner; in a few words