Taylor Swift to Katy Perry: Happy Birthday, Pretty Girl!

Taylor Swift and Dancing With The Stars pal Julianne Hough celebrate Katy Perry‘s 25th birthday at Sunset Beach in Los Angeles on Saturday (October 24).

The twosome painted their initials on each other!

Other celebs in attendance and pictured below: Chuck star Zachary Levi, Eastwick actor Matt Dallas and Joel Moore, who played Katy‘s date in her “Waking Up In Vegas” music video.

After the Willy Wonka and the Chocolate Factory extravaganza, Taylor tweeted, “@Katyperry knows how to throw a birthday party! I would even go as far as to say it was party-licious. Best EVER. Happy bday, pretty girl!!

FYI: Taylor is wearing a pretty white dress from Amy Claire and carrying a Lauren Merkin “Eve” clutch.

15+ pictures inside of Taylor Swift at Katy Perry‘s birthday bash…