They may be young, but they’re dominating streaming and driving the conversation, hitting 1 billion streams (Billie Eilish), reinvigorating indie rock (Snail Mail) and hooking Kanye up with his biggest hit in ages (Lil Pump).

METHODOLOGY: A committee of Billboard editors and reporters weighed a variety of factors in determining the 2018 21 Under 21 list, including but not limited to impact on consumer behavior, as measured by such metrics as album sales, track sales, streaming volume, social media impressions, and radio and TV audiences reached; company growth; career trajectory; reputation among peers; and overall impact in the industry specifically during the past 12 months. Where required, record-label market share was consulted using Nielsen Music market share for album plus track-equivalent and stream-equivalent album consumption units. Unless otherwise noted, Billboard Boxscore and Nielsen Music are the sources for tour grosses and sales/streaming data, respectively.

Contributors: Kat Bein, Tatiana Cirisano, Leila Cobo, Bianca Gracie, Lyndsey Havens, Tamar Herman, Steven J. Horowitz, Carl Lamarre, Taylor Weatherby.