Kylie Jenner is officially the youngest self-made billionaire. Here are 9 other self-made billionaires who crossed the $1 billion milestone before 30.

Forbes estimated Holmes to be worth $4.5 billion at age 30, in 2014, due to the massive valuation of her blood testing startup, Theranos. At the time, she was the youngest woman to become a self-made billionaire — and remained so until Jenner's recent triumph.

In 2016, Forbes dropped its estimate of Holmes' net worth to zero, due to allegations of fraud at Theranos.

The Facebook cofounder had a messy break with Mark Zuckerberg, but crossed the billion dollar milestone in 2010, thanks to his 5% stake in the social network.

Patrick Collison joined the elite ranks of people who become billionaires before turning 30 at age 28 in 2016. Stripe, an online payments company founded by Collison and his brother John, reached a $9.2 billion valuation after raising $150 million from Alphabet's investment division, pushing both brothers into billionaire range.

Snapchat cofounder Murphy passed the billionaire mark in 2015 at age 27, according to Forbes.

Moskovitz made Forbes' billionaires list for the first time in 2010, at the age of 26. While Moskovitz left Facebook in 2008, after serving as the first chief technology officer, his 6% stake in Facebook was almost entirely responsible for his place on the list.

John Collison was two years younger than his brother, Patrick, when both became billionaires in 2016.

The Snapchat CEO and co-founder was just 25 when he first earned a spot on Forbes' billionaires list in 2015.

Prior to this week, the Facebook cofounder and CEO was the youngest self-made billionaire, reaching $1 billion in 2008 at age 23.

Forbes estimated that Kylie Cosmetics, the company Jenner runs and owns, is worth $900 million.