Zhang was born in 1 April 1983. In 2001, he enrolled at Nankai University in Tianjin, where he majored in microelectronics before changing to software engineering, and graduated in 2005. He met his wife at university.

In February 2006, Zhang became the fifth employee and the first engineer at the travel website Kuxun (酷讯), and was promoted to technical director a year later.

In 2008, Zhang left Kuxun to work for Microsoft, but felt stifled by the corporate rules of the company. He soon left Microsoft to join the startup Fanfou (饭否), which eventually failed. In 2009, when Kuxun was about to be acquired by Expedia, Zhang took over Kuxun’s real estate search business and started 99fang.com (九九房), his first company.

In 2011, Zhang noticed the user migration from computers to smartphones. He hired a professional manager to take over as CEO of 99fang, and quit the company to start ByteDance in 2012.

Zhang thought that Chinese smartphone users were struggling to find information in mobile apps available in 2012 and the search giant Baidu was mixing search results with undisclosed advertising. His vision was to push relevant content to users using recommendations generated by artificial intelligence. This vision, however, was not shared by most venture capitalists, and he failed to secure funding until Susquehanna International Group agreed to invest in the startup. In August 2012, ByteDance launched the Toutiao news app and within two years attracted more than 13 million daily users. Sequoia Capital, which rejected Zhang the first time, came around and led a US$100 million investment in the company in 2014.

Zhang was named in the 2013 China 30 Under 30 list by Forbes. In 2018, he was included in Fortune magazine’s 40 Under 40 list. Zhang was named one of Time magazine’s 100 Most Influential People of 2019.

In September 2015, ByteDance launched its video sharing app TikTok (known as Douyin in China) with little fanfare. The product was an instant hit with millennials and became popular worldwide. ByteDance bought Musical.ly a year later for US$800 million and integrated it into TikTok.

ByteDance’s first app, Neihan Duanzi, was shut down in 2018 by the National Radio and Television Administration. In response, Zhang issued an apology stating that the app was “incommensurate with socialist core values”, that it had a “weak” implementation of Xi Jinping Thought, and promised that ByteDance would “further deepen cooperation” with the ruling Chinese Communist Party to better promote its policies.

In September 2020, the United States Department of Justice referred to Zhang as a “mouthpiece” of the Chinese Communist Party in a legal filing.