• Elon Musk became the world's first trillionaire after SpaceX's public debut.
• America has more billionaires than ever, led by Elon Musk and other tech executives.
• Figures such as John D. Rockefeller and Andrew Carnegie were known as the richest men of their time.

America has never had as many billionaires as it does now — and the number is only growing.

The SpaceX IPO resulted in one of the greatest wealth increases in history, turning Elon Musk's estimated net worth of over $800 billion before the company went public into the world's first-ever trillion-dollar-plus fortune.

While the scale of Musk's fortune is unprecedented by all measures, it also raises the question of how historic figures, largely considered America's richest, such as the Gilded Age industrialists, compare with the richest people today.

That is to say: Who are the richest Americans of all time?

In many historical calculations of net worth, individual fortunes weren't measured in isolation; instead, they were compared to the US GDP at the time.

When the US economy was much smaller than it is today, the wealthiest families and individuals carried more weight in the economy than others during more prosperous times.

One of the richest Americans of all time is widely considered to be Standard Oil founder John D. Rockefeller, whose wealth, at its peak in 1937, was equal to 1.5% of the country's GDP. His estimated net worth would be around $512.7 billion today, when adjusted for inflation.

Elon Musk's current wealth, however, has now far eclipsed that of Rockefeller's.

To identify some of the richest Americans of all time, we consulted Forbes' 2007 list of history's wealthiest figures, based on estimates by economist Peter Bernstein. It calculated individuals' wealth at their peak and compared it to the country's GDP at the time to convert it to 2006 dollars. This was then adjusted to today's dollars using the US Bureau of Labor Statistics' inflation calculator.

For living individuals, we cited Forbes' estimated net worths as of June 16, 2026.

While estimates of historical wealth may not be perfect, they help paint a picture of the wealth enjoyed by some of America's most notable business figures and put it in context with today's billionaires.

Here are 29 of the wealthiest Americans in history — and how modern-day tech magnates rank among them.

Andrew W. Mellon (1855-1937)

Estimated net worth (2026 adjusted estimate): $85.3 billion

Source of wealth: Banker and industrialist; heir to the Mellon banking dynasty

Henry Ford (1863-1947)

Net worth (adjusted estimate): $91.8 billion

Source of wealth: Automaker; founder of Ford Motor Company

Jay Gould (1836-1892)

Net worth (adjusted estimate): $98.4 billion

Source of wealth: Railroad financier and speculator

Sam Walton (1918-1992)

Net worth (adjusted estimate): $99 billion

Source of wealth: Retail entrepreneur; founder of Walmart

Marshall Field (1834-1906)

Net worth (adjusted estimate): $101.6 billion

Source of wealth: Retail magnate; founder of Marshall Field & Company

Bill Gates

Net worth: $104.4 billion

Source of wealth: Tech entrepreneur; cofounder of Microsoft

Thomas Peterffy

Net worth: $107.1 billion

Source of wealth: Digital trading pioneer; founder and former CEO of Interactive Brokers

Michael Bloomberg

Net worth: $109.4 billion

Source of wealth: Financial data entrepreneur; founder of Bloomberg LP

Frederick Weyerhaeuser (1834-1914)

Net worth (adjusted estimate): $122 billion

Source of wealth: Timber magnate; founder of Weyerhaeuser

Steve Ballmer

Net worth: $126 billion

Source of wealth: Tech executive; former CEO of Microsoft

Alice Walton

Net worth: $127.7 billion

Source of wealth: Walmart heir

Alexander Turney Stewart (1803-1876)

Net worth (adjusted estimate): $136.6 billion

Source of wealth: Retail pioneer; founder of AT Stewart & Co.

Jim Walton

Net worth: $136.7 billion

Source of wealth: Walmart heir and board member

Richard B. Mellon (1870-1933)

Net worth (adjusted estimate): $139.1 billion

Source of wealth: Banker and industrial investor; heir to Mellon banking dynasty

Rob Walton

Net worth: $139.4 billion

Source of wealth: Walmart heir and former chairman

Warren Buffett

Net worth: $146.4 billion

Source of wealth: Investor; former CEO of Berkshire Hathaway

Stephen Girard (1750-1831)

Net worth (adjusted estimate): $161.6 billion

Source of wealth: Banker, merchant, and financier

Jensen Huang

Net worth: $181.1 billion

Source of wealth: Co-founder and CEO of Nvidia

John Jacob Astor (1763-1848)

Net worth (adjusted estimate): $186.1 billion

Source of wealth: Fur trader and real-estate investor

Mark Zuckerberg

Net worth: $204.7 billion

Source of wealth: Tech entrepreneur; cofounder of Facebook, now Meta

Michael Dell

Net worth: $229.2 billion

Source of wealth: Tech entrepreneur; founder and CEO of Dell Technologies

Larry Ellison

Net worth: $238.3 billion

Source of wealth: Software entrepreneur; cofounder and former CEO of Oracle

Jeff Bezos

Net worth: $255.6 billion

Source of wealth: E-commerce entrepreneur; founder of Amazon

Sergey Brin

Net worth: $279.6 billion

Source of wealth: Tech entrepreneur; cofounder of Google

Cornelius Vanderbilt (1794-1877)

Net worth (adjusted estimate): $284.6 billion

Source of wealth: Shipping and railroad tycoon

Larry Page

Net worth: $303.1 billion

Source of wealth: Tech entrepreneur; cofounder of Google

Andrew Carnegie (1835-1919)

Net worth (adjusted estimate): $475.2 billion

Source of wealth: Steel industrialist; founder of Carnegie Steel

John D. Rockefeller (1839-1937)

Net worth (adjusted estimate): $516 billion

Source of wealth: Oil magnate; founder of Standard Oil

Elon Musk

Net worth: $1.4 trillion

Source of wealth: Tech entrepreneur; CEO of Tesla and SpaceX

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