Arriving on the red carpet in a cropped top and high-waist matching skirt, showing off her pins in a pair of Christian Louboutin heels, Katy looked flippin' flawless.
The 28-year-old paired the frock with blue nails, gold accessories and her hair swept over one eye (the superhero look, basically).
Katy is said to have split from John, 35, this week, but looked unfazed by her heartache as she posed for the paps and signed autographs for fans.
She took to Twitter before her arrival to show off her pre-red carpet brave face, tweeting: "Live every day like you're gonna be wiped out by a meteor. #scienceyolo."
And the outfit definitely paid off, with Katy looking so hot when she took to the stage to accept her Favourite Female Singer award that she was mobbed by award presenters, Big Time Rush.
Things got a little awkward when the boys started fighting over who got to cuddle Katy first and then refusing to let go, leaving Katy to prize herself away and straighten out her dress.
Picking up her trophy, she told the crowd: "I love the kids! Stay in school and stay safe."
Katy and John apparently split this week, blaming "work commitments" as the reason for their demise.
A source said: "it's sad, but it's not over until it's over. You have to see how things play out."
Katy later tweeted that she was listening to Kacey Musgraves' album to get her through the break-up, admitting that it "makes everything better".
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