burn off vs burn up

burn off and burn up both are verbs.

Word	Noun	Adjective	Verb	Adverb
burn off	No	No	Yes	No
burn up	No	No	Yes	No

As verbs, burn off and burn up are synonyms defined as:

Other synonyms of burn off include burn.

burn off (verb)	burn up (verb)
clear land of its vegetation by burning it off	burn completely; be consumed or destroyed by fire
use up (energy)	use up (energy)
	burn brightly