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They say life begins at 40 — until then, you're just doing research! Take a look at all the stars celebrating the big 4-0 this year…
Karolina Kurkova celebrates her 40th birthday on Feb. 28.
More than a decade ago, the Czech supermodel revealed that she experienced early menopause at age 24 and gained 30 pounds due to an issue with her thyroid: "I was 24 and going through menopause — that was one of my side effects. I thought I was going crazy. I was having panic attacks every minute and I didn't know what was happening, because I've been a healthy person. I've exercised all my life. I've always eaten well and taken care of myself," she said back in 2012.
Keep reading to see more stars who were born in 1984 …
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In 2019, Olivia Wilde's directorial debut, "Booksmart," premiered at South by Southwest on her 35th birthday, March 10. Five years later, she's directed another feature film — the controversial "Don't Worry Darling" — and is set to helm the upcoming comedy "Naughty" in 2024, according to Deadline.
Olivia, who turns 40 on March 10, has also already confronted plenty of ageism, thanks to critics of her "Don't Worry Darling"-era romance with Harry Styles, who is 10 years her junior.
Asked about the ageist social media backlash in 2022, Olivia told ELLE, "It's so interesting for me when that comes from women because I'm like, 'Do you plan on not getting older? Or if you already are older, do you feel that you don't deserve the same opportunities in life?' It's so sad to me to look at that and realize people have such small expectations for their own lives and they are projecting those expectations onto me. And I reject your projections."
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Kate McKinnon turned 40 on Jan. 6 just weeks after she returned to "Saturday Night Live" to host for the first time in December 2023. Prior to her hosting debut, the beloved comic appeared on "SNL" for a whopping 11 seasons from 2012 to 2022.
"All I ever wanted to do in my whole life was be on 'Saturday Night Live,'" the Emmy winner said on "Live With Kelly and Ryan" after leaving the show. "So I did, I loved it, I had the best decade, and then I was just like, my body was tired, and I felt like it was time."
Kate's departure cleared room on her schedule for her already-iconic performance as Weird Barbie in 2023's "Barbie" blockbuster film. (Even with her mismatched clothes, scribbled-on face and habit of suddenly doing creepy splits, Weird Barbie still ends up giving Stereotypical Barbie some of her most essential advice.) Kate's Weird Barbie was such a hit, in fact, that she inspired her very own Mattel doll.
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Having made her mark as the longest running female cast member on "Saturday Night Live," Cecily Strong moved on from the show in 2022 after 11 and a half seasons.
She kicked off 2024 with her 40th birthday on Feb. 8, just two days after performances begin for her latest off-Broadway show, "Brooklyn Laundry."
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Singer, actress and Broadway alum Katharine McPhee enters her 40s on March 25, one month after her son, Rennie, turns 3. The former "American Idol" star shares Rennie with her husband, Grammy-winning music producer David Foster.
The two are famously 34 years apart in age. While Katharine kicks off her 40s in 2024, David, who's also a dad to five adult children, turns 75 on Nov. 1.
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Jack Antonoff, whose music producing credits range from Taylor Swift and Lana Del Rey to Diana Ross, the Chicks and the 1975, turns 40 on March 31.
Looking back on his younger self in 2023, a few months after he and actress Margaret Qualley tied the knot, Jack told The Guardian: "When I was 20 years old, my brain was on fire. I was really messy, emotionally. What I know now is this: If something in your gut says no, then it's no." Live and learn!
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Mandy Moore turns 40 on April 10, and she's all about adding another candle to the cake: "I'm excited about all the collective wisdom and clarity and giving less of a you-know-what as you get older," the singer and "This Is Us" star told Parade in 2020.
"Already, the older I am, the more comfortable I get in my skin. You couldn't pay me money to go back to the last decade of my life," she added. "The 20s were the worst!"
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On the first two seasons of Netflix's "The Crown," Claire Foy played a young Queen Elizabeth II, portraying the monarch in her 20s through her late 30s.
The Emmy winner, who was in her 30s herself during her time on the show, greets 40 on April 16.
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From her work in "Ugly Betty" to "Barbie," America Ferrera's been winning our hearts for decades. She turns 40 on April 18 with an Emmy, a Golden Globe, a SAG Award and more honors under her belt.
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It's easy to forget just how young Mark Zuckerberg was when he got his start in tech, but the Meta CEO and Facebook co-founder formed his first software programming company, Intelligent Media Group, when he was still in high school.
Since then, he's been credited with changing the course of how we use the internet, both for better and, in some cases, for worse. Time magazine named him one of the most influential people in the world in 2008, 2011, 2016 and 2019, and crowned him Time Person of the Year in 2010. As of January 2024, his estimated net worth stood at a cool $122 billion. That was all before age 40, a landmark the controversial tech star hits on May 14.
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Former "The Daily Show" host Trevor Noah marked his 40th trip around the sun on Feb. 20. Following his Emmy-winning tenure with Comedy Central, the South Africa-born star embarked on a world tour, launched a new Spotify podcast, "What Now? With Trevor Noah," and released both an album, "I Wish You Would," and a Netflix special, "Trevor Noah: Where Was I."
Trevor's milestone birthday comes on the heels of his fourth straight year hosting the Grammy Awards, where "I Wish You Would" was up for best comedy album.
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Aubrey O'Day turned 40 on Feb. 11. One person who won't make the guest list for her birthday bash? Donald Trump Jr.
The singer and reality star reportedly had an affair with former President Donald Trump's eldest child in 2011 and 2012 after they met on the set of "The Celebrity Apprentice." A decade later, Aubrey called Don Jr. her "soulmate" and said that she will "always have love for him," though she claimed she was "so disappointed in what he became" after he broke up with her to "go be the president's son."
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Emmy-winning actress, writer and producer Lena Waithe turns 40 in 2024: The "Queen & Slim" screenwriter celebrates her landmark birthday on May 17.
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"Parks and Recreation" star Aubrey Plaza, who later lent her famous deadpan deliveries and sarcastic expressions to HBO's "The White Lotus," turns 40 on June 26.
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On June 27, Khloe Kardashian becomes the third sibling in her famous family to turn 40. Sister Kim Kardashian marked the same milestone in 2021, one year after sibling Kourtney Kardashian, who turned 40 in 2020.
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Fantasia Barrino, who starred in "The Color Purple" on Broadway and recently reprised her role in the 2023 film adaptation, marks 40 trips around the sun on June 30.
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Best known for playing Jane Villanueva on The CW's "Jane the Virgin," Gina Rodriguez — who welcomed her first child with husband Joe LoCicero in 2023 — welcomes a new decade on July 30 when she turns 40.
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Canadian pop-punk star Avril Lavigne was just 17 when she released 2002's "Let Go" featuring hits like "Complicated." Fast forward to Sept. 27, 2024, and the teenage voice behind "Sk8r Boi" turns 40.
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When Prince Harry's wife, Meghan Markle, turned 40 in 2021, she marked the milestone by launching a mentorship campaign for women re-entering the workforce.
Now it's Harry's turn. The Duke of Sussex turns 40 on Sept. 15, and while his plans for the big day have yet to be announced, something tells us the Invictus Games and Archewell co-founder's philanthropic endeavors will be involved.
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Katy Perry marks her 40th spin around the sun on Oct. 25. In 2023, the pop star and mom celebrated her special day on "American Idol," where her fellow judges presented her with a cake.
"I know what I'm wishing for," she said as she blew out the candles. "I'm wishing for peace."
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Rapper T-Pain, who revolutionized the use of Auto-Tune — a pitch processor Cher famously used on her 1988 dance hit "Believe" — marks his milestone 40th birthday on Sept. 30.
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On Oct. 18 — 16 years after her breakout performance in "Slumdog Millionaire" hit theaters — actress Freida Pinto turns 40.
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Conservative news star Meghan McCain welcomes Scorpio season when she turns 40 on Oct. 23. Following her infamous 2021 departure from "The View," Meghan released her memoir, "Bad Republican," and began contributing op-ed pieces to DailyMail.com.
Reflecting on her time on "The View" on a 2023 episode of her podcast, Meghan said (per Entertainment Weekly), "I just felt like I could not be the kind of mother, wife and commentator I wanted to be in that kind of a chaotic environment."
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"10 Cloverfield Lane" and "Scott Pilgrim vs. the World" star Mary Elizabeth Winstead turns 40 on Nov. 28. The actress and singer shares a son, Laurie, with husband Ewan McGregor, whom she met on the set of "Fargo."
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In 2022, Scarlett Johansson told Vogue, "I feel more like myself the older I get." The following year, the Oscar-nominated "Lost in Translation" star and mother of two was named the highest grossing box office actor in the world. ScarJo turns 40 on Nov. 22.
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Los Angeles Lakers star — and the new face of Louis Vuitton in 2024 — LeBron James celebrates his 40th birthday on Dec. 30. The NBA's all-time leading scorer, "King James," made his pro hoops debut back in 2003.
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Grammy-winning singer and Oscar-nominated actress Andra Day shares a birthday with LeBron James. The "United States vs. Billie Holiday" star wraps up 2024 with a 40th birthday on Dec. 30.
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Abbi Jacobson — who funneled the hilarious misadventures of her 20s into the hit series "Broad City" alongside bestie Ilana Glazer — is officially older and wiser in 2024: The co-creator and star of Amazon's "A League of Their Own" turned 40 on Feb. 1.
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Kid Cudi, born Scott Ramon Seguro Mescudi, rang in his 40th birthday on Jan. 30 after an intense 2023 that saw him release what he's said could be his last album: "Insano."
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Scottish DJ and producer Calvin Harris celebrated his 40th on Jan. 17. The EDM artist then kicked off a busy few months including a string of performances to carry him into festival season and around the world.
Calvin, who famously dated Taylor Swift from 2015 to 2016, tied the knot with British TV and radio presenter Vick Hope in northeast England in September 2023. The couple's wedding featured performances by Nile Rodgers and Chic and what The Sun described as a "Glastonbury-style afterparty."
Looking ahead to the new year — with his 40th less than a month away — Calvin hopped on Instagram on Jan. 1, writing, "Happy 2024!!!!! Buzzing for it!"
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