40 Under 40: The Richest Self-Made Billionaires Under 40 |
In 2008, Mark Zuckerberg became the youngest self-made billionaire ever at age 23. Six years later, he overtook Google cofounders Larry Page and Sergey Brin as the world’s richest self-made billionaire under 40 on Forbes’ annual World’s Billionaires List. The Meta chief held onto that title for a record 11 straight years before aging out in May 2024 when he turned 40. That made room for brothers Patrick Collison, 37 and John Collison, 35, of Stripe to claim that crown on Forbes’ latest annual ranking in March, though their reign didn’t last long.
As of this Fall, there’s a new richest self-made billionaire under 40: Surge AI’s 38-year-old founder Edwin Chen, who is worth an estimated $18 billion. He is one of 27 new self-made billionaires under the age of 40 to have minted three-comma fortunes just since March when Forbes locked in our 2025 World’s Billionaires List; nearly half of these newcomers made their money in AI.
Altogether, Forbes found 71 billionaires aged 39 or younger who built their own fortunes (rather than inheriting them) as of December 2025. The only other time the number of Under 40 self-made billionaires was this high was amid the Covid-fueled stock market craze that led to a record 71 on the 2021 list–it later bottomed out at 34 in 2023 after the bubble burst and a number of billionaires aged out.
All but 11 of today’s young billionaire entrepreneurs made their money in tech (48) or finance and investments (12). Just under half (or 32) of them are American; citizens of China (8), India (6), Australia (3), Sweden (3) and Canada (3) round out the top 6. Eight are women.
There is still one area where this group falls short of the 71 self-made billionaires under age 40 in 2021: total net worth. Today’s 71 self-starters control $218 billion of wealth combined, a staggering sum but only about half the 2021 group’s $444 billion total fortune, led by Zuckerberg who himself was worth $97 billion at the time.
The wealthiest self-made billionaire under 40 today, Surge AI’s Chen, is worth about a fifth as much as Zuckerberg was back in 2021. Tied for the last two spots in this year’s top 40 are DoorDash’s Andy Fang and crypto exchange Bullish’s Brendan Blumer, who are each worth $1.8 billion. That’s a high enough bar to keep out a bunch of big names like 36-year-old Taylor Swift (estimated fortune: $1.6 billion) and 37-year-old Rihanna ($1 billion), who both missed the cut. Also falling outside the top 40 are some of the youngest billionaires: prediction markets startup Kalshi’s 29-year-old cofounder Luana Lopes Lara ($1.3 billion), a former ballerina from Brazil who became the world’s youngest self-made woman billionaire in December, and AI recruiting startup Mercor’s three 22-year-old cofounders, who became the youngest self-made billionaires ever in October.
Time will tell who among this young crop has staying power like Sergey Brin, Michael Dell and Mark Zuckerberg did before them, and who will flame out like Luminar Technologies’ founder and former CEO Austin Russell, who was reportedly ousted in May after an internal ethics inquiry, and FTX’s Sam Bankman-Fried, who is serving out a 25-year prison sentence for orchestrating multiple fraudulent schemes. One sure bet: there will be winners and losers.
Here are the 40 richest self-made billionaires under the age of 40
Chen founded artificial intelligence startup Surge AI in 2020 to help companies label data for AI training. He serves as CEO of the company, which generated $1.2 billion of revenue in 2024 from customers like Google and Anthropic. A graduate of MIT, where he studied math, computer science and linguistics, Chen claims to have grown Surge without raising any outside funding. Forbes estimates that Chen owns three-quarters of the firm.
Wang founded China-based toy company Pop Mart International Group in........