self-assurance vs confidence

self-assurance and confidence both are nouns.

Word	Noun	Adjective	Verb	Adverb
self-assurance	Yes	No	No	No
confidence	Yes	No	No	No

As nouns, self-assurance and confidence are synonyms defined as:

self-assurance and confidence: freedom from doubt; belief in yourself and your abilities

Other synonyms of self-assurance include assurance, authority, self-confidence, sureness.

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