add up vs add together

add up and add together both are verbs.

Word	Noun	Adjective	Verb	Adverb
add up	No	No	Yes	No
add together	No	No	Yes	No

As verbs, add up and add together are synonyms defined as:

Other synonyms of add up include add, sum, sum up, summate, tally, tot, tot up, total, tote up.

add up (verb)	add together (verb)
determine the sum of	make an addition by combining numbers
be reasonable or logical or comprehensible	determine the sum of
to measure up to in kind or quality
add up in number or quantity