The 'Atonement' star has said that she doesn't worry about the way she looks and only thinks about it if that starts affecting her acting career, reported Contactmusic.
"I never even think about beauty. Supposedly being pretty is a double-edged sword, your look gets you certain roles, but disqualifies you from others. That's the way the industry goes," she said.
The 29-year-old actress, who married The Klaxons musician James Righton, 30, last year, revealed that she was a tomboy when growing up and showed any interest in make-up until she was 14.
"Transforming yourself is also part of an actor's job. On the one hand, there's the public image of me, and on the other, a private person," she added.
Keira is currently the face of Chanel's Coco Mademoiselle fragrance.