confidence vs certainty

confidence and certainty both are nouns.

Word	Noun	Adjective	Verb	Adverb
confidence	Yes	No	No	No
certainty	Yes	No	No	No

As nouns, certainty is a hypernym of confidence; that is, certainty is a word with a broader meaning than confidence:

confidence (noun)	certainty (noun)
freedom from doubt; belief in yourself and your abilities	something that is certain
a secret that is confided or entrusted to another	the state of being certain
a feeling of trust (in someone or something)
a state of confident hopefulness that events will be favorable
a trustful relationship