Khloé Kardashian Wears Jaw-Dropping Cutout Dress for Star-Studded White Party on Fourth of July

Khloé Kardashian made a splash at Michael Rubin's annual White Party in the Hamptons for the Fourth of July.

The reality star, who turned 40 on June 27, stepped out to the star-studded bash in a white figure-hugging dress with a high neckline and sexy cutout details. Her waist-length light brown hair was styled into soft waves and she wore a simple, glowy makeup look.

Khloé attended the Thursday, July 4, gathering alongside her sister Kim Kardashian, who wore a sleek white skirt and matching halter-style top with a plunging neckline. The SKIMS founder accessorized with a large silver cross necklace. The sisters matched in almond-shaped French manicures. Younger sister Kendall Jenner was also in attendance.

Rubin, the CEO of the online retail company Fanatics, has hosted the annual White Party in celebration of the Fourth of July since 2021. The lavish affair is held at his Hamptons estate in Long Island, N.Y., and is regularly attended by a slew of A-listers.

This year's guest list included Drake, Megan Thee Stallion, Emily Ratajkowski, Megan Fox, Machine Gun Kelly and Tom Brady.

On Saturday, June 29, Khloé threw a saloon-themed party — with a denim and diamonds dress code — for her 40th birthday. The Good American co-founder celebrated with her sisters Kim, Kourtney Kardashian and Kylie Jenner, as well as other celebrities like Sara Foster and Kimora Lee Simmons. Guests enjoyed performances by rappers Snoop Dogg, Warren G and Kurupt.

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For the festivities, Khloé wore a diamond-encrusted bustier corset and matching denim jeans and accessorized with plenty of diamond necklaces.

The Kardashians star also rang in her milestone birthday with a new, brunette hair color. She shared the transformation with fans on Snapchat, saying that her previous strawberry blonde shade was "too much maintenance."

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"Okay, so I colored my hair again," she said, showing off her mid-tone brown locks streaked with subtle with honey highlights. "My hair was red for, I don't know, like a month or so I would say... and as much as I love red, every single time you wash it, it comes out, it fades color. Towards the end, my hair was, like, honey, maybe strawberry, very light strawberry blonde."

Khloé continued, "Anyways, more power to all the redheads out there, you guys are dedicated. I have been platinum blonde and that is so much easier for me than the red. The red was just too much maintenance."