words per minute vs wpm

words per minute and wpm both are nouns.

Word	Noun	Adjective	Verb	Adverb
words per minute	Yes	No	No	No
wpm	Yes	No	No	No

As nouns, words per minute and wpm are synonyms defined as:

words per minute and wpm: the rate at which words are produced (as in speaking or typing)

words per minute (noun)	wpm (noun)
the rate at which words are produced (as in speaking or typing)	the rate at which words are produced (as in speaking or typing)