From paperboy to vacuum salesman, the unglamorous early jobs of 15 CEOs

Before he was running a $4 trillion company, Nvidia CEO Jensen Huang was washing dishes and waiting tables at a Denny's in Portland, Oregon. He got his first job at the diner when he was 15, and, years later, batted around the initial ideas behind Nvidia at a Denny's in Northern California.

Now, Huang is worth $163.6 billion.

Michael Dell, the CEO of Dell Technologies, took a gig washing dishes at a Chinese restaurant when he was 12. Today, he's worth $140.8 billion.

Berkshire Hathaway CEO Warren Buffett is notoriously frugal, despite being worth $148.2 billion. Buffett got his first job delivering newspapers as a teenager. Ever the businessman, he invested some of those savings.

Mary Barra is the CEO of General Motors, but she got her start on the assembly line at the age of 18. She spent her time inspecting the hoods and fenders of the vehicles.

As the founder, former CEO, and current executive chair of Amazon, Jeff Bezos is worth $243.8 billion. But he spent his teenage summers working the grill at McDonald's.Door

"The most challenging thing was keeping everything going at the right pace during a rush," Bezos told author Cody Teets. "The manager at my McDonald's was excellent. He had a lot of teenagers working for him, and he kept us focused even while we had fun."

Elon Musk, who has cofounded and runs several companies, left his home in South Africa at the age of 17. He stayed with his cousin in Canada, where he tended to vegetables and grain bins on a farm, according to the book "Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future." After visiting an unemployment office, Musk ended up cleaning the boiler room at a lumber mill, the book says.

Musk is now the world's richest man, worth $749.7 billion.

Doug McMillon started his career at the same company he now leads: Walmart. For his first job, he unloaded trucks at a Walmart Distribution Center in Arkansas.

Before co-founding and becoming the CEO of Netflix, Reed Hastings went door-to-door selling vacuums. He's now Netflix's chairman and is worth $5.2 billion, but has said he looks back fondly on that time.

Bob Iger, the CEO of Disney, started out as a weatherman in Ithaca, New York, before moving to New York City to work at Disney-owned ABC.

When billionaire entrepreneur Mark Cuban was 12, he said he asked his dad if he could get a pricey pair of sneakers. His dad told him to get a job. That's when one of his dad's friends chimed in and said he needed to sell some garbage bags, so the not-yet-teenage Cuban went door-to-door.

Cuban is now worth $6 billion.

Jan Koum, cofounder and former CEO of WhatsApp, immigrated to Mountain View, California, when he was 16. While there, he swept floors at a local grocery store to help his mom pay their bills. Now, Koum is worth $17.2 billion.

The former Yahoo CEO began her career as a grocery store clerk in Wisconsin when she was in high school. She led Yahoo from 2012 to 2017, and is now worth $1.3 billion.

Former CEO of Bloomberg and mayor of New York City, Michael Bloomberg, parked other people's cars while in college. He used the job as a summer parking attendant to help pay his way through Johns Hopkins. Bloomberg is now worth $109.4 billion.

Apple CEO Tim Cook started working when he was 12, delivering newspapers in the early morning hours before sneaking in a nap before school. He said that the job helped "start my college education."

Now, Cook is worth $2.6 billion.

Abigail Johnson's father was the CEO of Fidelity Investments, but he had her start at the bottom of the corporate ladder, taking customers' orders. She took the job the summer before college, before eventually returning and working her way up to CEO in 2014.

"I was responsible for filling out the forms to correctly put in order the transactions that they were requesting," Johnson told Fortune. "It was a pretty basic job. But it gave me an appreciation of what it was like to be responsible for really important things in people's lives and making sure that they were always done accurately and correctly."

Johnson is now worth $35.6 billion.