peachy vs not bad

peachy and not bad both are adjectives.

Word	Noun	Adjective	Verb	Adverb
peachy	No	Yes	No	No
not bad	No	Yes	No	No

As adjectives, peachy and not bad are synonyms defined as:

Other synonyms of peachy include bang-up, bully, corking, cracking, dandy, great, groovy, keen, neat, nifty, old, slap-up, smashing, swell.

peachy (adjective)	not bad (adjective)
of something resembling a peach in color	excellent
excellent