How to Say "self-assurance" in Spanish
The Spanish word for “self-assurance” is “seguridad” — B1 level. This is a very common word in everyday Spanish.
English → SpanishB1
NounB1
Confidence in one's own abilities or character.

Examples
Habló con mucha seguridad durante la entrevista.
He spoke with a lot of confidence during the interview.
Necesitas tener más seguridad en ti misma.
You need to have more confidence in yourself.
Tengo la seguridad de que todo saldrá bien.
I have the certainty that everything will turn out well.
'Seguridad' vs. 'Confianza'
Mistake: “Using 'confianza' when you mean certainty.”
Correction: 'Seguridad' is best when you are sure of a fact. 'Tengo la seguridad de que 2+2=4.' (I'm certain that 2+2=4). 'Confianza' is more about trust in a person or process. 'Tengo confianza en ti.' (I trust you).
Related Translations
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