Ari Staprans Leff (born August 8, 1994), known professionally as Lauv, is an American singer, songwriter and record producer based in Los Angeles. His debut EP Lost in the Light was released in 2015 and his compilation album I Met You When I Was 18 (The Playlist) was released in 2018. He has written songs for other artists including the singles "Boys" by Charli XCX, "No Promises" by Cheat Codes and Demi Lovato and "Imperfections" by Celine Dion.
Lauv was born in San Francisco, California. He spent his early childhood in a suburb of Atlanta, Georgia, before his family relocated to a suburb of Philadelphia, Pennsylvania. He went to Radnor High School. As a child, he was interested in music and took piano and viola lessons before learning how to play the guitar at the age of 11. He started writing songs in middle school, at around 14 years old. During his time in high school, he played in several bands and studied jazz before moving on to electronic music. He has said that his sister would drive him and his friends on tour, where they often played "to zero people."
After graduating high school, Leff decided to pursue a behind-the-scenes role in music. He chose to study music technology at New York University's Steinhardt School. While at university, he studied abroad in Prague and was a member of the Zeta Psi fraternity. He spent two of his four years at NYU as a studio intern for Jungle City Studios, where artists such as Jay-Z, Justin Timberlake, and Alicia Keys recorded.