Cool for the summer? Changing up your hairstyle, which is exactly what several celebrities recently decided to do. 

Should you be itching to chop some inches off your hair, may we suggest taking a look at Zendaya's chic new bob, which was definitely giving Rachel from Friends energy. And, if you're looking to get in the fall mood a little early, Hailey Bieber is serving up her latest treat-inspired beauty trend: Cinnamon cookie butter strands. 

Elsewhere, Vanderpump Rules' Tom Schwartz took a cue from Barbie's Ken and went platinum blonde, while Keke Palmer showed off her most dramatic hair transformation yet. Plus, Brian Austin Green clapped back at commenters after he shaved his head, proving he had 9021-zero time for anyone's hot takes. 

Finally, Blac Chyna impressed fans when she shared an update from her ongoing wellness journey, including her time up in the gym just working on her fitness.

Check out the most surprising celeb transformations of the week...

The one where Zendaya paid homage to Friends.

The Dune star showed off a new 'do on her Instagram Story after getting "a little refresh" on Aug. 22, rocking a shorter layered haircut similar to the one made famous by Jennifer Aniston as Rachel Green on the iconic NBC sitcom.

However, this isn't the first time Zendaya has opted to go short, first debuting a caramel-colored bob at a Euphoria event in December of last year. At the time, she playfully addressed her chop by sharing a meme of the character Agent Wendy Pleakley from the 2002 Disney film Lilo & Stitch with the text, "When bitches get a lil bob."

Forget glazed donuts, there's a new yummy treat to take beauty inspo from this fall.

The Rhode Beauty founder is ready for the upcoming season change, thanks to her fresh new hair color, which she debuted on Instagram Aug. 15.

"We named it 'cinnamon cookie butter,'" Bieber's hairstylist Matt Rez captioned a snap of the toned down hue, adding the leaf, cookie and butter emojis.

This Ken needs a pumptini.

The Vanderpump Rules star entered his Barbie era when he ditched his brunette locks for a freshly dyed blonde 'do. Schwartz debuted a platinum blond hair transformation while out at the Mondrian hotel in Los Angeles on Aug. 12.

In an Instagram photo posted by a fan named Amanda, the TomTom owner showed off his Kenergy wearing a black sweater and black pants as he flashed a smile. Amanda captioned the snapshot, "blondes have more fun."

Blac Chyna is committed to her goals. 

The reality star showed off the results of her fitness routine amid her ongoing wellness journey, which has included getting sober and having several cosmetic fillers dissolved. Chyna took to Instagram on Aug. 20 to post a video of her time in the gym, doing ab exercises and working a leg press machine.

"Mind, Body, and Soul all combined there's endless possibilities," Chyna captioned the clip. "Be safe God bless you all."

We're definitely saying yes to this new look.

The Nope star debuted her most dramatic hair transformation yet, showing off a layered bob with curtain bangs in an Aug. 14 Instagram post.

"You think you down," Palmer captioned the pic, "but you ain't serious."

9021-Zero opinions are necessary!

After shaving his head for an upcoming role, Green took to Instagram to debut his new look. "Fresh cut," he captioned the Aug. 5 post. "Thought I'd share."

The Beverly Hills, 90210 alum went on to share that the buzzcut was "for work," addressing previous comments weighing in on his  transformation, explaining, "since people seem to want to comment about their opinion on it."

Pretty in pink.

The Pretty Little Liars: Original Sin star switched up her hair color, debuting a Barbie-approved bubblegum hue on Aug. 7.

"We went Pink!" Madison's hairstylist Scott King captioned his Instagram post, adding the hashtag "#pinkhairdontcare."

Madison reposted the photo to her Instagram Story, revealing she and King had been taking about making the color change "forever," explaining that it "felt like the perfect time to finally do it."