how long did it take gangnam style to get a billion views
4 months
Gangnam Style
Gangnam Style" debuted at number one on South Korea's Gaon Chart. The song and its music video went viral in August 2012 and have influenced popular culture worldwide. In the United States, "Gangnam Style" peaked at number two on "Billboard" Hot 100. By the end of 2012, "Gangnam Style" had topped the music charts of more than 30 countries including Australia, Canada, France, Germany, Italy, Russia, Spain, and the United Kingdom.

A music video was released the same day, attracting global media attention and a public audience. In September 2012, "Gangnam Style" was recognized by "Guinness World Records" as the most "liked" video on YouTube at the time. It subsequently won Best Video at the MTV Europe Music Awards held that year. It became a source of parodies and reaction videos by many different individuals, groups and organizations. On 21 December 2012, "Gangnam Style" became the first YouTube video to reach one billion views. 
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Gangnam Style [SEP] Introduction
"Gangnam Style" (, ) is a song by South Korean singer Psy, released on 15 July 2012 by YG Entertainment as the lead single of his sixth studio album, "Psy 6 (Six Rules), Part 1". A K-pop and dance-pop song, the term "Gangnam Style" is a Korean neologism that refers to a lifestyle associated with the Gangnam District of Seoul. The song received mixed reviews, with praise for its catchy beat and Psy's amusing dancing (which has itself become a phenomenon) in the music video and during live performances in various locations around the world. "Gangnam Style" debuted at number one on South Korea's Gaon Chart.