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Millie Bobby Brown, 17 -

The actress became one of the youngest Emmy nominees in history at age 13 for her role as Eleven in 'Stranger Things.' Add to that the fact that she's the youngest person to be nominated as a UNICEF Goodwill Ambassador, and it's easy to forget she's just a teen!

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Willow Smith, 21 -

All this time under the spotlight and the youngest Smith has just entered her twenties! She's the youngest artist to ever be signed to Jay-Z's label, Roc Nation, and she emanates an old wisdom that can be seen in interviews and on  'Red Table Talk' alongside her mother, Jada Pinkett Smith. 

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Yara Shahidi, 21 -

It's enough that she started her career at age six, but the actress also speaks on important social and political issues with an eloquence that far exceeds what most can accomplish in their twenties.

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Bella Thorne, 24 -

Actress, singer, model, author, adult-film director—and all before she turned 23.

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Shawn Mendes, 23 -

The Canadian singer-songwriter first struck fame in 2013 posting videos to social media, when he was just 15.

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Camila Cabello, 24 -

Cabello's journey with Fifth Harmony and her subsequent solo career make it feel like she is a seasoned artist, and she is in many ways, but she's still barely into her twenties.

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Chloë Grace Moretz, 24 -

Moretz started acting when she was just six, so 18 years in the industry surely has something to do with it.

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Zendaya, 25 -

From music to TV, modeling to film, Zendaya has done so much before the age of 25 you'll just have to read about it here.

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Lorde, 25 -

Lorde has been playing on the radio for what seems like ages, but her age makes more sense when you consider that her first album came out when she was just 16.

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Hailee Steinfeld, 24 -

She turns 25 in December, and could retire if she wanted to. She was nominated for an Academy Award when she was just 13 years old, she's since starred in movies like 'Pitch Perfect' and 'The Edge of Seventeen,' and she's become a pop star too.

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Bella Hadid, 25 -

The world-famous model has appeared on runways all over the world and had a high-profile relationship with singer The Weeknd, making it hard to believe she only turned 25 in October.

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Kylie Jenner, 24 - A reality TV star, a CEO, a billionaire, and a mother, all before the age of 23!

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Kendall Jenner, 26 -

Like her little sister, Kendall Jenner has been in the press from such a young age that we forget the now world-famous model just turned 26 in November.

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Sophie Turner, 25 -

As a star of not one but two beloved fantasy worlds (‘Game of Thrones’ and ‘X-Men’), as well as a wife and now a mother, many forget Turner hasn’t even passed her mid-twenties.

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Gigi Hadid, 26 -

Gigi Hadid has had a successful modeling career for years now, appearing on magazine covers and closing runway shows. And she's also a mom!

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Halsey, 27 -

Besides being a consistent hitmaker in recent years, Halsey has been a leading voice in the conversation about mental health, exuding a maturity that most people twice her age haven't achieved.

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Justin Bieber, 27 -

It's not so much the maturity with Justin Bieber (he's certainly lived out some reckless phases), but it's how much he's accomplished and for how long, remaining in the spotlight for over a decade.

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Saoirse Ronan, 27 - The actress landed her big break, 'Atonement,' when she was 13, and since then she's earned four Oscar nominations, so it's safe to say Ronan has had a richer career than most of us already.

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Meghan Trainor, 27 -

Trainor turns 28 in December, and has certainly had far too much success to still be in her twenties.

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Ariana Grande, 28 - Though she does have somewhat of a baby face, the singer's voice and career to date are certainly not that of an average twenty-something.

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Miley Cyrus, 29 -

From Disney's 'Hannah Montana' to real-life pop superstar, to divorcee and back, it feels like Cyrus has been around forever, but she only turned 29 in November.

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Sam Smith, 29 -

The singer first rose to fame in 2012, when they were just 22.

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Selena Gomez, 29 -

From her success in Hollywood with Disney, more serious films, and as a pop star, to her mental health activism, her work with UNICEF, and her candid struggle with lupus, Gomez is Tinseltown's ultimate old soul.

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Cara Delevingne, 29 -

When you start modeling at 10, it's easy for people to mistake you as someone much older than you are.

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Shailene Woodley, 30 -

After first finding fame as the lead on ABC series 'The Secret Life of the American Teenager,' Woodley has been nominated for nearly all the major awards, and she's made a name for herself as an environmental activist, all long before hitting 30.

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Jennifer Lawrence, 31 -

At just 22, J-Law was the second-youngest winner of the Academy Award for Best Actress in 2012, which explains why she's only just hit 31 this year.

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Margot Robbie, 31 -

Knowing that Robbie landed the role of Leonardo DiCaprio's love interest in 'The Wolf of Wall Street' when she was just 23 makes it easier to believe that she just hit 31 in 2021.

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Hayden Panettiere, 32 -

Having had her big break at age five on 'One Life to Live,' Panettiere has had a long career onscreen, so it's surprising she's only 32 this year.

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Lady Gaga, 35 -

From bursting onto the scene in her envelope-pushing looks, to transitioning from pop music to actress and back, it's hard to believe Lady Gaga is still in her thirties.

See also: Actors who were way too young or too old for their roles.

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