The Keeping Up With The Kardashians star did a quick switch inside the Montage Beverly Hills Hotel on Wednesday (12 November), where she was gathered with friends and family to celebrate Kourtney's third pregnancy.
Khloe, 30, arrived at the glam Breakfast At Tiffany's-themed bash in a striking supertight white pencil skirt and crop top combo.
But leaving a few hours later, she'd changed into a decidedly less glamorous combination of black leggings, jumper and trainers.
Off to the gym, perhaps?
Khloe admitted in September that she'd gained 10lbs while filming her new E! show in The Hamptons over the summer and would be hitting the gym hard on her return to LA.
She showed off the results of her gruelling workouts in that super tight ensemble at yesterday's baby shower, which was also attended by sisters Kim Kardashian and Kylie Jenner.
Reveal is now on Google Plus! Join us here for the latest pictures, fashion and celebrity news!