Jack Patrick Dorsey: Twitter Founder’s Bio and Career

Jack Patrick Dorsey is the American technology entrepreneur who co-founded Twitter and later launched the payments company Square, now called Block. Born on November 19, 1976, he is 49 as of early November 2026 and turns 50 later this month.

Quick facts

A coder from St. Louis

Dorsey grew up in St. Louis and became interested in computers as a teenager, writing dispatch routing software that was used by taxi companies. He studied at Missouri University of Science and Technology and later moved to New York University, though he did not finish a degree, before heading to California to pursue tech work.

The birth of Twitter

In 2006, working with Biz Stone, Evan Williams and Noah Glass at the podcasting company Odeo, Dorsey helped build a short-message service inspired in part by dispatch and SMS. The first tweet, “just setting up my twttr,” was posted by Dorsey on March 21, 2006. The platform grew quickly through events such as SXSW and eventually became a central venue for news, politics and pop culture.

Leadership at Twitter

He served as the company’s CEO in its early period, left the role in 2008, and returned in 2015 as the company struggled to find footing. He led Twitter through its stock market era and a number of public debates about moderation, free speech and misinformation. He stepped down as CEO in November 2021 and left the board in 2022, shortly before Elon Musk acquired the company.

Square and Block

In 2009 Dorsey co-founded Square with Jim McKelvey, creating a small card reader that let small businesses accept payments through smartphones. The company expanded into Cash App, small-business tools and, later, bitcoin-focused products. In December 2021 it was renamed Block, reflecting its widening scope. Dorsey has run it as CEO.

Bitcoin, Bluesky and open protocols

Dorsey has become one of the best-known corporate backers of Bitcoin, and he has argued for open, decentralized communication systems. He supported the development of Bluesky, which began as a Twitter-funded project, and has promoted decentralized protocols such as Nostr. His views on the future of social media have regularly drawn attention.

How his wealth works

His fortune comes primarily from his stakes in Twitter before its sale and, above all, from holdings in Block, so estimates move with the stock price. Business publications have at various times placed his wealth in the billions, but we avoid quoting a single figure because it changes constantly.

Personal style

He is recognized for a distinctive beard, a minimalist lifestyle and practices such as meditation and intermittent fasting, which he has described in interviews.

Giving and public statements

In 2020 Dorsey pledged a large amount of his Square shares, reported as about one billion dollars, to a fund called Start Small, which supported COVID-19 relief and later other causes. The commitment was widely covered and gave a sense of how much of his wealth sits in company stock rather than cash.

Leadership style

Dorsey has run two public companies at the same time, a rarity in tech that drew criticism from investors, who argued he was stretched thin. Supporters countered that he had a rare view of both social networks and financial technology. His management style, as described in profiles, is quiet and thoughtful, with a preference for short meetings and written notes.

Reading the wealth claims

Any article that gives you one precise net worth number is out of date by the time you read it. Block’s share price rises and falls, and Dorsey holds a large share of his wealth in the company. That’s why we describe his fortune in terms of sources rather than a single figure.

What fans and critics ask

The questions you see most are whether he still has a role at Twitter (no, and the platform is now called X), what Block does (payments, Cash App, bitcoin-related tools and music streaming through Tidal), and how he approaches Bitcoin (he has described it as a tool for open, global money). People also ask why he left, and his own explanation was that the company should be able to function without a founder.

Frequently asked questions