"I'm a Big Girl Now" is a novelty song written by Al Hoffman, Milton Drake, and Jerry Livingston.
[1][2] It was recorded in 1946 by American bandleader Sammy Kaye with vocals by singer Betty Barclay.
[2][3][4] Released as a single by RCA Victor, Kaye's recording was a commercial success in the United States, topping The Billboard's Best-Selling Popular Retail Records chart in the issue dated April 27, 1946.
[6] According to Drake, "I'm a Big Girl Now" was written at the request of Kaye, who had recently recruited Barclay to sing with his band and sought a "special" song to debut at their first public performance together.
Its lyrics are addressed to the singer's boyfriend, conveying to him her desire to no longer be treated as a child.