Jack Dorsey, the co-founder of Twitter and mobile payments giant Block, Inc. (formerly Square), has carved out a unique path in the tech world as a pioneering entrepreneur and philanthropist. As of 2025, Dorsey’s estimated net worth is $4 billion, making him one of the wealthiest innovators in Silicon Valley. At 48 years old, Dorsey’s fortune is split between his significant holdings in Block and other investments, including cash and assets, despite market fluctuations and public scrutiny.
Early Life and Background
Born on November 19, 1976, in St. Louis, Missouri, Jack Dorsey showed early signs of curiosity and talent in technology. While attending Bishop DuBourg High School, he became fascinated with dispatch software used by taxis and emergency services. By the age of 15, he had written a dispatch program that some cab companies continued to use well into the future.
Dorsey’s knack for problem-solving was further demonstrated when, at 17, he hacked into New York City’s largest taxi dispatch company to expose a vulnerability. Instead of facing legal consequences, he was offered a job, prompting a move to New York City where he briefly studied at NYU before transitioning into the tech startup world.
The Birth of Twitter
Dorsey’s entrepreneurial breakthrough came in 2006 during a brainstorming session at Odeo, a podcasting company founded by Evan Williams. Collaborating with Williams, Biz Stone, and Noah Glass, Dorsey helped conceive the idea of a microblogging platform initially dubbed “twttr.” His initial prototype involved sending short status updates using BlackBerry devices, laying the groundwork for what would become Twitter.
Twitter launched in 2006 and faced skepticism from some quarters, criticized as trivial in its early days. Yet, the platform rapidly grew in influence, playing a crucial role in real-time communication during political campaigns, social movements, and global events. Under Dorsey’s leadership as CEO and later executive chairman, Twitter became one of the most recognizable social media platforms worldwide.
When Elon Musk acquired Twitter in April 2022 for $44 billion, Dorsey owned about 18 million shares, approximately 2% of Twitter’s total stock. This resulted in a payout of nearly $974 million when the deal closed at $54.20 per share.
Square’s Evolution Into Block
While Twitter solidified Dorsey’s reputation, it was his second company, Square, that became the major driver of his personal wealth. Co-founded in 2009 with Jim McKelvey, Square (now Block, Inc.) aimed to make credit card payments accessible for small businesses via a compact card reader attached to smartphones or tablets.
Square went public in 2015 at a valuation of $3 billion. Over the next six years, it became a fintech powerhouse, expanding into digital wallets, peer-to-peer payments via Cash App, and cryptocurrency services. In February 2021, Square’s market cap crossed $100 billion, significantly boosting Dorsey’s net worth to an estimated $16 billion at that time, with roughly $15 billion attributed to his Square holdings.
As of 2025, Dorsey owns about 43 million shares of Block, Inc., valued at around $2.5 billion. His position in Block remains the core of his net worth despite a $500 million dip in 2023 following a short-seller report by Hindenburg Research, which targeted the company’s business practices and caused its stock price to decline temporarily.
Philanthropy: A Billion-Dollar Pledge
In April 2020, amid the COVID-19 pandemic, Dorsey pledged $1 billion worth of his Square shares—approximately 28% of his wealth at the time—to a charitable initiative called Start Small LLC. The fund focuses on global COVID-19 relief efforts, universal basic income (UBI), education, and women’s health initiatives.
Dorsey’s philanthropic activities have been notable not just for their size but also for their transparency. The Start Small LLC maintains a public Google Doc detailing every donation made. Major contributions include $10 million to Boston University’s Center for Antiracist Research and $15 million to COVID-19 relief efforts in India.
By the end of 2020, Start Small had donated over $274 million, while retaining millions in Square shares, which appreciated further despite stock volatility.
Leadership Style and Controversies
Dorsey’s unconventional leadership style has been a point of both admiration and criticism. Known for being a minimalist and practicing wellness routines like intermittent fasting and meditation retreats, Dorsey has often drawn scrutiny for his perceived detachment from Twitter’s day-to-day operations. In 2019, he publicly stated his goal to visit at least 30 of Twitter’s global offices, all while balancing responsibilities at both Twitter and Square.
Dorsey stepped down as Twitter’s CEO in November 2021, citing the need to focus on Block and other ventures. Following Twitter’s acquisition by Elon Musk in 2022, Dorsey became more actively involved in Bluesky Social, a decentralized social media platform he co-founded as an offshoot of Twitter aimed at creating open-source, censorship-resistant networks.
Real Estate and Personal Life
While Dorsey has kept much of his personal life private, his real estate portfolio offers some insight into his lifestyle. In 2018, he purchased a home in the Hollywood Hills for $4.22 million, which he later sold for $4.6 million.
His primary residence is a sprawling compound in San Francisco. In 2012, he acquired a $10 million home overlooking the Golden Gate Bridge and, in 2017, expanded his property by purchasing the neighboring house for $22 million. Despite his billionaire status, Dorsey is known to live modestly and has been seen walking several miles to work when residing in San Francisco.
Legacy in Tech and Beyond
Jack Dorsey’s contributions to social media and financial technology are undeniable. He is among the few entrepreneurs who have successfully co-founded two publicly traded companies that redefined their respective industries. While Twitter has shaped global discourse and real-time communication, Block continues to play a critical role in democratizing financial services for small businesses and individuals.
With a focus on decentralized platforms like Bluesky and his ongoing philanthropic efforts, Dorsey’s impact extends far beyond corporate success. In an industry often criticized for prioritizing profits over social good, Dorsey stands out as a tech leader who continues to blend innovation with social responsibility.