At the beginning of To Kill a Mockingbird, Scout Finch is six years old.
Scout—whose adult name is Jean Louise Finch—narrates the story retrospectively, but the opening events are experienced by her as a six-year-old child in Maycomb, Alabama. Her older brother, Jem, is four years older, creating the sibling dynamic that shapes much of the novel.
Scout ages from six to nine over the book’s roughly three-year span. This is why some readers remember her as older: the adult narrator’s vocabulary and insight are far more sophisticated than a young child’s, while the events themselves unfold through her childhood perspective.
Her age also matters thematically. Scout initially responds to insults and injustice with a child’s directness, often fighting or asking Atticus questions, before gradually developing a more mature understanding of prejudice and empathy.