Ranked: The 10 Youngest U.S. Billionaires on the Forbes 400Key TakeawaysSeven of America’s 10 youngest Forbes 400 billionaires built their fortunes in AI.Anthropic accounts for four of the 10, with their combined fortunes totaling an estimated $62 billion.Nine of the 10 are self-made, but the lone heir, Lukas Walton, is the richest at $44.4 billion.Artificial intelligence isn’t just creating some of America’s most valuable startups. It’s also creating a new generation of billionaires.The 2026 Forbes 400 includes founders and executives behind Anthropic, OpenAI, Surge AI, and Cognition among its youngest members, highlighting how quickly AI wealth has risen into the upper ranks of America’s richest people.This visualization ranks the 10 youngest members of the Forbes 400 by age and shows the companies behind their fortunes. Net worth figures are as of Sept. 4, 2026, and a fortune of at least $4.4 billion was required to make this year’s Forbes 400.How AI Is Reshaping America’s Youngest BillionairesThe youngest person in the group is 30-year-old Steven Hao, cofounder of AI coding company Cognition, with an estimated fortune of $5.8 billion. At the other end of the ranking, several billionaires are 39 years old, including Walmart heir Lukas Walton and Anthropic cofounders Daniela Amodei and Tom Brown.NameAgeNet Worth (Billions)Source of Wealth: Steven Hao30$5.8BCognitionPalmer Luckey33$5.9BAndurilSam McCandlish36$15.5BAnthropicJack Clark37$15.5BAnthropicGreg Brockman38$25.5BOpenAIEdwin Chen38$18.0BSurge AIDaniela Amodei39$15.5BAnthropicTom Brown39$15.5BAnthropicVlad Tenev39$7.1BRobinhoodLukas Walton39$44.4BWalmartSeven names on the list made their fortunes in AI. The remaining fortunes come from Walmart, fintech company Robinhood, and defense technology company Anduril.Four Anthropic Cofounders Are Worth $15.5 Billion EachAnthropic accounts for four of the 10 youngest billionaires: Sam McCandlish, Jack Clark, Daniela Amodei, and Tom Brown.Forbes estimates that each holds a stake worth $15.5 billion, putting their combined fortunes at roughly $62 billion. The four range in age from 36 to 39.Other AI fortunes include OpenAI cofounder Greg Brockman, whose estimated net worth stands at $25.5 billion, Surge AI founder Edwin Chen at $18 billion, and Cognition cofounder Steven Hao at $5.8 billion.Most of These Fortunes Are Tied to Private CompaniesAnother defining feature of the ranking is how much of the wealth comes from private companies. Eight of the 10 fortunes are based on private-company stakes valued using recent funding rounds, according to the source note accompanying the Forbes data.Unlike public stocks, private companies don’t have continuously traded market prices. New funding rounds can reset company valuations and significantly change the estimated paper wealth of major shareholders.That dynamic is especially important for privately held AI companies, where rising valuations have created multibillion-dollar fortunes well before many of these businesses have reached the public markets.The Only Heir Is Also the RichestFor all the new wealth being created in technology, the richest person in the ranking represents a much older source of billionaire wealth.NameSource of Wealth: Self-made or inheritedSteven HaoCognitionSelf-madePalmer LuckeyAndurilSelf-madeSam McCandlishAnthropicSelf-madeJack ClarkAnthropicSelf-madeGreg BrockmanOpenAISelf-madeEdwin ChenSurge AISelf-madeDaniela AmodeiAnthropicSelf-madeTom BrownAnthropicSelf-madeVlad TenevRobinhoodSelf-madeLukas WaltonWalmartInheritedAt 39, Lukas Walton has an estimated net worth of $44.4 billion stemming from retail giant Walmart. He is the only person among the 10 whose fortune is identified as inherited.His fortune also stands above every individual AI billionaire shown.The ranking captures two very different paths to extreme wealth within the same generation: a decades-old retail fortune at the top and a wave of newer fortunes built around some of the world’s fastest-growing technology companies.Learn More on the Voronoi AppIf you enjoyed today’s post, check out The World’s Richest Person Every Year Since 1987 on Voronoi, the app from Visual Capitalist.