Happy birthday, Calvin Klein!

Today, the New York-based fashion designer turns 72. His eponymous company has become a household name since its inception in 1968, which isn't surprising considering how common Klein's designs are on the red carpet and how many celebrity endorsers the company's got.

In honor of the legendary designer's special day, here are 7 celebrities who love Calvin Klein.

READ MORE: Calvin Klein Underwear: What Is 'Plus-Size?'

Justin Bieber

It's no secret what brand of underwear Justin Bieber wears. The constantly shirtless singer loves showing off his body - whether it be through Instagram selfies or otherwise - and most recently stripped down to his Calvin Klein undies at the 2014 Fashion Rocks charity fundraiser event in September.

Kendall Jenner

Reality star and model Kendall Jenner is also a big fan of all things Calvin Klein. In March, Jenner posted a picture of her wearing a bra and briefs given to her by the company on Instagram.

Since then, rumors have been flying around that she and Bieber are starring in some sort of ad campaign for Calvin Klein - although there's been no confirmation of any sort on that front.

Mark Wahlberg

Before Nick Jonas and before Justin Bieber, there was "Marky Mark," who - with a backwards CK hat and a little bit of crotch-grabbing - became one of Calvin Klein's most well-known celebrity endorsers with his infamous 1992 underwear ads.

Emma Watson

Emma Watson loves her Calvin Klein on the red carpet. The actress stunned with a custom-made dress at the "Harry Potter and the Deathly Hallows - Part 1" (2010) premiere in New York and was honored with the Calvin Klein Collection Emerging Star Spotlight Award at the 19th Annual Women in Hollywood Celebration in 2012.

Olivia Wilde

Olivia Wilde's another big fan of Calvin Klein, having attended the designer's fall fashion show in New York last year and wearing a series of gorgeous Calvin Klein dresses at red carpet events like the 2013 Met Gala.

Scarlett Johansson

Back in 2004, Scarlett Johansson became the face of a new Calvin Klein fragrance called "Eternity Moment" and starred in a TV commercial alongside British actor and model Trent Ford.

The "Avengers" star also loves to wear the designer's dresses at red carpet events like the 2004 Met Gala and the Golden Camera Awards in 2012. 

Zoe Saldana

Fellow Marvel movie star Zoe Saldana is also a celebrity endorser for Calvin Klein. In 2010, she became the face of the brand's Envy underwear line.

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