American Idol is an American singing competition television series created by Simon Fuller, produced by Fremantle North America and 19 Entertainment, and distributed by Fremantle North America. It aired on Fox from June 11, 2002, to April 7, 2016, for 15 seasons. It was on hiatus for two years until March 11, 2018, when a revival of the series began airing on ABC.

It started as an addition to the Idols format that was based on Pop Idol from British television, and became one of the most successful shows in the history of American television. The concept of the series involves discovering recording stars from unsigned singing talents, with the winner determined by American viewers using phones, Internet, and SMS text voting. The winners of the first twenty seasons, as chosen by viewers, are Kelly Clarkson, Ruben Studdard, Fantasia Barrino, Carrie Underwood, Taylor Hicks, Jordin Sparks, David Cook, Kris Allen, Lee DeWyze, Scotty McCreery, Phillip Phillips, Candice Glover, Caleb Johnson, Nick Fradiani, Trent Harmon, Maddie Poppe, Laine Hardy, Just Sam, Chayce Beckham, and Noah Thompson.

American Idol employs a panel of vocal judges who critique the contestants' performances. The original judges, for seasons one through eight, were record producer and music manager Randy Jackson, singer and choreographer Paula Abdul, and music executive and manager Simon Cowell. The judging panel for the last three seasons on Fox consisted of singers Keith Urban, Jennifer Lopez, and Harry Connick Jr. Season sixteen brought three new judges: singers Lionel Richie, Katy Perry, and Luke Bryan. The first season was hosted by radio personality Ryan Seacrest and comedian Brian Dunkleman, but Seacrest has been the sole host since the second season.

The success of American Idol has been described as "unparalleled in broadcasting history". A rival TV executive said the series was "the most impactful show in the history of television". It became a recognized springboard for launching the career of many artists as bona fide stars. According to Billboard magazine, in its first ten years, "Idol has spawned 345 Billboard chart-toppers and a platoon of pop idols, including Kelly Clarkson, Carrie Underwood, Chris Daughtry, Fantasia, Ruben Studdard, Jennifer Hudson, Clay Aiken, Adam Lambert, and Jordin Sparks while remaining a TV ratings juggernaut." For an unprecedented eight consecutive years, from the 2003–04 television season through the 2010–11 season, either its performance show or result show was ranked number one in U.S. television ratings.