check out vs check into

check out and check into both are verbs.

Word	Noun	Adjective	Verb	Adverb
check out	No	No	Yes	No
check into	No	No	Yes	No

As verbs, check out and check into are synonyms defined as:

check out and check into: examine so as to determine accuracy, quality, or condition

Other synonyms of check out include check, check over, check up on, go over, look into, suss out.

check out (verb)	check into (verb)
examine so as to determine accuracy, quality, or condition	examine so as to determine accuracy, quality, or condition
announce one's departure from a hotel
try to learn someone's opinions and intentions
record, add up, and receive payment for items purchased
withdraw money by writing a check
trace
be verified or confirmed; pass inspection