Greczyn was born in Walnut Creek, California and lives in Hollywood, California. She was home-schooled and started taking classes at Front Range Community College when she was 15. Informed that she had to be 18 to study nursing, she decided to try modeling and relocated to California. Greczyn is of European and Asian descent.
Greczyn started her career with a role in the movie Sleepover. She later appeared in the Fox comedy show Quintuplets as a recurring character. She was also cast in the short lived show Windfall. Greczyn played a recurring character on both Lincoln Heights and Privileged. Greczyn was cast in a supporting role for the 2004 comedy Fat Albert and appeared in the 2005 movie The Dukes of Hazzard. In 2007, Greczyn appeared in the horror movies House of Fears and Shrooms. The following year she appeared in the comedy, Sex Drive and the action movie Exit Speed. Greczyn acted in Make It or Break It for three episodes, playing a model struggling with anorexia. Greczyn is scheduled to be the model for Victoria Beckam's denim and eyewear line.
- Exit Speed (2008) as Annabel Drake
- Sex Drive (2008) as Mary
- An American in China (2008) as Kendra
- House of Fears (2007) as Candice
- Shrooms (2007) as Holly
- The Lying Game (2011) as Madeline Rybek