How many letters does the top answer for “freedom from doubt; belief in yourself and your abilities” have?

The most common answer is assurance (9 letters).

Crossword clue: freedom from doubt; belief in yourself and your abilities

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

assurance 9 letters wn-def

freedom from doubt; belief in yourself and your abilities

confidence 10 letters wn-def

freedom from doubt; belief in yourself and your abilities