- Dec 1 Yolandi Visser, South African rapper (Die Antwoord), born in Port Albert, South Africa
- Dec 5 Lera Lynn, American singer-songwriter (True Detective), born in Houston, Texas
- Dec 8 Sam Hunt, American country pop singer (Take Your Time), born in Cedartown, Georgia
- Dec 15 Joshua Hayward, British rock guitarist (The Horrors), born in Southend-on-Sea, Essex, England
- Dec 20 David Tavaré, Spanish pop-eurodance singer ("Hot Summer Night (Oh La La La)"), born in Pollença, Spain
- Dec 22 Basshunter [Jonas Erik Altberg], Swedish record producer and DJ (Now You're Gone), born in Halmstad, Sweden
- Dec 24 Jehnny Beth [Camille Berthomier], French musician, singer-songwriter (John & Jehn; Savages; To Love Is to Live), born in Poitiers, France
- Dec 25 Jessica Origliasso, Australian singer-songwriter and actress (The Veronicas), born in Albany Creek, Queensland, Australia
- Dec 25 Lisa Origliasso, Australian singer-songwriter and actress (The Veronicas), born in Albany Creek, Queensland, Australia
- Dec 27 Pleasure P. [Marcus Cooper], American R&B singer (Pretty Ricky), born in Miami, Florida
- Dec 30 Andra Day [Cassandra Batie], American singer-songwriter ("Rise Up"), and actress (The United States vs. Billie Holiday), born in Edmonds, Washington
- Dec 30 Dalia Stasevska, Ukrainian-Finnish conductor (Lahti Symphony, 2021-present), born in Kyiv, Ukrainian SSR, USSR (now Ukraine)
About December 1984
How Old? 39 years old
Generation: Millennial
Leap Year: Yes
Chinese Zodiac: Rat
Star Signs: Sagittarius (Nov 22 - Dec 21), Capricorn (Dec 22 - Jan 19)