Tim Sweeney

Sweeney was raised in Potomac, Maryland, the youngest of three brothers. At a young age, he became interested in tinkering with mechanical and electrical devices, and stated he had taken apart a lawnmower as early as five or six, and later built his own go-kart. He became interested in arcade games when they began to become popular in the late 1970s, knowing that like the mechanical devices he took apart and repaired, there were those that had programmed the games in the machines. Though the family got an Atari 2600, Sweeney was not as interested in the games for that, outside of Adventure, and later said he had not played many video games in his life and very few to completion.

At the age of 11, Sweeney visited his older brother's new startup in California, where he had access to early IBM Personal Computers. Sweeney spent the week there, learning BASIC and establishing his interest in programming; while he had had a Commodore 64 before, Sweeney was much more taken by how easy the IBM PC was to use. When his family got an Apple II, Sweeney began in earnest learning how to program on that, trying to make Adventure 2 in the spirit of the Atari 2600 game. Sweeney estimated that between the ages of 11 and 15, he spent over 10,000 hours teaching himself how to program using information on online bulletin boards, and completed several games, though never shared these with others. He also learned from his brothers' concepts of entrepreneurship. As a teenager, he made a good deal of money by offering to mow lawns of wealthy residents in the area for half the price of professional services.

Sweeney lives in Cary, North Carolina. According to Forbes, as of May 2022, he has a net worth of $7.6 billion. However, Bloomberg estimates his wealth at $9.6 billion.

Since 2006, Sweeney has filed several patents related to computer software.

Since the real estate bubble collapsed in 2008, Sweeney has used his fortune to purchase large tracts of land in North Carolina, reportedly for conservation, becoming one of the largest private landowners in the state. As of November 2025, he has bought 50,000 acres of forest land including the Box Creek Wilderness, a 7,000-acre natural area that contains more than 130 rare and threatened plants and wildlife species. Sweeney, who had paid $15 million for Box Creek Wilderness, donated the conservation easement to the United States Fish and Wildlife Service in 2016. One of the motives to put Box Creek Wilderness under conservation easement was a condemnation lawsuit filed by a power company who planned to build a transmission line through the land. The lawsuit was settled following the Fish and Wildlife Service's and Senator Richard Burr's involvement in protecting the site, which prevented it from being fragmented. "I'm grateful for the efforts of Senator Burr to help protect Box Creek Wilderness," Sweeney said. "And for the whole Fish and Wildlife Service team's tireless efforts to preserve vital North Carolina natural areas in partnership with conservation-minded landowners like me."

Additionally, he has participated in the expansion to Mount Mitchell State Park by donating 1,500 acres (610 ha) to a conservation project.

In April 2021, it was announced that Sweeney would donate 7,500 acres in the Roan Highlands of western North Carolina to the Southern Appalachian Highlands Conservancy. When transferred the next year, the conservancy will manage the property as a nature preserve, conducting scientific studies in collaboration with Sweeney and offering guided hikes. This acreage, valued at tens of millions of dollars, is the largest private conservation land donation in the history of North Carolina. Over nearly two decades, he has used his wealth to conserve natural land and later transfer it to conservation groups, prioritizing environmental protection over profit or publicity.