Kylie Jenner is officially the youngest self-made billionaire of all time, snatching the title from founder.

Jenner, 21, was finally given the title after months of speculation on Tuesday by Forbes as it unveiled its annual billionaire'sKylie JE 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.

That's a nice pat on the back
Kylie Jenner on becoming the world's youngest self-made billionaire

'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.

Only two of the star's sisters congratulated her success. Kendall, her closest in age, posted on Twitter and Instagram in support of her whereas Kim tweeted her pride.