As he has done every year since 2007, DJ Earworm takes the year's 25 biggest pop songs and turns them into a magical mash-up that he calls the "United State of Pop."

"Personally, I've been obsessed with the Billboard charts since I was 11 or 12," Earworm (real name: Jordan Roseman) tells Billboard about the tradition he started in 2007. "When I was a little boy, I used to tune in to Top 40 shows on the weekends, and I've always been fascinated by what makes popular tastes tick … It's great to be able to come full-circle with Billboard." (Source: Billboard.com)

Earworm said this year's 25 songs are more "contemplative" than past years so he had to take the tempo of his mashup down.

Earworm told Billboard he used drums from Jessie J’s "Bang Bang," the percussion of DJ Snake & Lil Jon’s "Turn Down For What," the horns from Jason Derulo's "Talk Dirty" and the piano hooks from A Great Big World's "Say Something."

The songs that are mashed up in the video, according to HuffPo, are:

  • A Great Big World feat. Christina Aguilera - "Say Something"
  • Ariana Grande feat. Iggy Azalea - "Problem"
  • Bastille - "Pompeii"
  • Dj Snake & Lil Jon - "Turn Down For What"
  • Hozier - "Take Me to Church"
  • Idina Menzel - "Let It Go"
  • Iggy Azalea feat. Charli XCX - "Fancy"
  • Iggy Azalea feat. Rita Ora - "Black Widow"
  • Jason Derulo feat. 2 Chainz - "Talk Dirty"
  • Jeremih feat. YG - "Don't Tell 'Em"
  • Jessie J feat. Ariana Grande & Nicki Minaj - "Bang Bang"
  • John Legend - "All Of Me"
  • Katy Perry feat. Juicy J - "Dark Horse"
  • Lorde - "Team"
  • Magic! - "Rude"
  • Maroon 5 - "Animals"
  • Meghan Trainor - "All About That Bass"
  • Nico & Vinz - "Am I Wrong"
  • One Direction - "Story of My Life"
  • Passenger - "Let Her Go"
  • Pharrell Williams - "Happy"
  • Pitbull feat. Ke$ha - "Timber"
  • Sam Smith - "Stay With Me"
  • Taylor Swift - "Shake It Off"
  • Tove Lo - "Habits"