American Top 40

American Top 40 (often abbreviated to AT40) is a United States-based internet radio station located in Los Angeles, California, that plays a Contemporary Hit Radio (CHR) format, focusing on the latest pop, dance, and hip-hop hits. It is an internationally syndicated, independent song countdown radio program created by Casey Kasem, Don Bustany, Tom Rounds, and Ron Jacobs. American Top 40 with Ryan Seacrest typically airs on weekend mornings on KIIS‑FM, following the show’s syndicated schedule. While it is a syndicated show heard on hundreds of stations globally, its “home” and flagship presence in the United States is deeply rooted in Los Angeles. The station is now distributed by Premiere Networks. Although it is heard everywhere, the show is produced and recorded in the Los Angeles area (Burbank/Hollywood).