Karly is a modern spelling of Carly, the feminine short form of Carl or Charles, which goes back to the Germanic word karl and means "free man" or, for a girl, "free woman". The spelling with K spread in the United States in the late 20th century alongside Carly and Karlie. Karly peaked at number 698 in 2000, dropped out of the top 1000 soon after and has slipped to number 2631 in 2025, with 66 girls given the name.