Jenner, 21, was finally given the title after months of speculation on Tuesday by Forbes as it unveiled its annual billionaires list.
At 21, she is both the youngest self-made billionaire and the youngest billionaire on Forbes’ ‘young billionaires’ list.
Jenner has amassed a personal net worth of $1billion through her wildly successful range of make-up, Kylie Cosmetics.
She overtakes Zuckerberg, who was 23 when he made his first billion 11 years ago in 2008.
Now, he is the eighth richest person in the world with a fortune of $62.3billion.
Jenner is the youngest in her famous, reality TV family and the first to hit the billion dollar landmark.
She was surprised by the success of her cosmetics company which was only founded in 2015 but is now worth an estimated $900million.
Jenner, who owns a 100 percent stake in it, has separate income from endorsements and her family’s reality TV show. She also owns an impressive portfolio of real estate.
‘I didn’t expect anything. I did not foresee the future. But [the recognition] feels really good.
‘That’s a nice pat on the back,’ Jenner told Forbes.
She credits her success to her enormous social media following which ensured her customer base before she made her first product.
‘It’s the power of social media. I had such a strong reach before I was able to start anything,’ she said, adding that she sees the company going ‘very far’.
‘I see [Kylie Cosmetics] going very far. I work really hard,’ she said.
Her mother Kris would not rule out that she may sell the company in the future.
‘It’s always something that we’re willing to explore,’ she said.
Amazon mogul Jeff Bezos remains the richest man in the world with an estimated fortune of $131billion.
When his divorce to his wife MacKenzie is finalized, he will likely be knocked from the top spot.
Also on the list of young billionaires is Snapchat founder Evan Spiegel.
At 28, he has amassed a fortune of$2.1billion.
He, Jenner and John Collison, 28, are the only self-made billionaires on the young list this year.
Collison is the founder of the Irish payment company Stripe. He is worth $2.1billion.
Sisters Alexandra and Katharina Andresen, aged 22 and 23, are also on the list.
The Norweigan sisters are heiresses to their father’s holding company, Ferd S, and they each now have a personal fortune of $1.4billion.
Seven of the 10 richest people in the world are American. All are men.
The richest woman in the world is Francoise Bettencourt Meyers who, along with her family, has a fortune of $49.3billion. They own a 33 percent stake in L’Oreal.
Donald Trump is the first billionaire president of the United States. He is the 715th richest person in the world with a net worth of $3.1billion.
Tesla founder Elon Musk is the 40th wealthiest person in the world with a net worth of $22.3billion.