Happy Birthday, Britney Spears! See the Star's Best Beauty Moments Through the Years

Happy birthday, Britney Spears! The performer rings in her 33rd year today. It seems like just yesterday that the one-time brunette shot to stardom with her single "Baby One More Time" at the age of 16. Since then, the Princess of Pop has delivered chart-topping hits and best-selling fragrances, has launched a lingerie and sleepwear collection, and has even delved into acting with her leading role in 2002's Crossroads, opposite Zoe Saldana and Taryn Manning, and her stint on How I Met Your Mother.

The Grammy winner currently headlines her own Vegas show (she's had the residency for the past year) and plans to stick around through 2016. It's been a whirlwind career for Spears—who as a working mom to sons Sean, 9, and Jayden, 8, makes it look seamless—and her recipe for success couldn't be more straightforward. She tells InStyle, "Finding balance and happiness—and being healthy" are the keys to a fulfilled life.

PHOTOS: Britney Spears's Transformation