By Meghan Blalock
Updated Aug 30, 2012 @ 10:15 am
Credit: Kevin Mazur/WireImage; Visual/FameFlynet Pictures; Intertopics/Retna Ltd.; Rex/Rex USA

Cameron Diaz turns 40 today! And the blue-eyed beauty is happy to celebrate this momentous milestone. “Life gets better as you get older, definitely," she told InStyle for her May cover story. "I don't want to be 20! I feel better than ever: stronger, more capable, and clearer. I really know myself now." Here's to hoping she has her best birthday yet!

Plus, see more stars who turned 40 this year!