Her rep confirmed the engagement to AP, but did not have additional details.
The Oscar-nominated 27-year-old actress and Righton, keyboardist for the Klaxons band, started dating early last year.
Knightley is starring with Steve Carell in the upcoming dramedy, “Seeking a Friend for the End of the World,” in theaters June 22. She recently wrapped a film adaptation of the classic Tolstoy novel, “Anna Karenina.”
In 2008, Forbes named Knightley as the 2nd highest paid actress, having reportedly earned $32M in 2007.
Actress Keira Knightley and musician boyfriend James Righton are getting married.