21 Under 21 Playlist: 5 Seconds of Summer, Fifth Harmony & More of the List's Greatest Hits

Billboard's 2015 21 Under 21

This year's 21 Under 21 list -- our annual look at the hottest artists in all genres who can't yet legally purchase alcohol -- includes bubblegum divas, punky boy bands, plucky country pairs, two types of rap duos, and one very large K-pop ensemble. The 21 creators celebrated below all make different types of tunes, but they've all achieved great things in their relatively short time on this planet.

Check our playlist of the greatest hits from this year's list:

21. Shamir: "On The Regular"

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20. Kehlani: "The Way /(feat. Chance the Rapper)

19.  Echosmith: "Cool Kids"

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18. Seventeen: "Jaga Slahu Hatimu"

17. Silento: "Watch Me (Whip/Nae Nae)"

16. Luis Coronel: "Nada Mas por Eso"

15. Jack & Jack: "California"

Vine Stars Jack & Jack Make Rap Chart Debut

14. Austin Mahone: "Dirty Work"

13. Zendaya: "Replay"

12. Becky G: "Break a Sweat"

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11. Alessia Cara: "Here"

10. Hailee Steinfeld: "Love Myself"

9. Joey Bada$$: "Lose Control"

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8. Maddie & Tae: "Fly"

7. Martin Garrix: "Break Through The Silence"

6. Troye Sivan: "TALK ME DOWN"

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5. Rae Sremmurd: "This Could Be Us"

4. Shawn Mendes: "Stitches"

3. Lorde: "Royals"

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2. Fifth Harmony: "Worth It"

Fifth Harmony's Normani Kordei Stars in Future & Teyana Taylor's Music Videos: Watch

1. 5 Seconds of Summer: "She's Kinda Hot"

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