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For the first time, 1 billion people used Facebook in a day

FILE - In this March 25, 2015 file photo, Mark Zuckerberg talks about the Messenger app during the Facebook F8 Developer Conference in San Francisco. For the first time, a billion people used Facebook in a single day on Monday, Aug. 24, 2015. Zuckerberg marked the occasion with a post on his Facebook page, saying that one out of seven people on Earth logged in to the social network to connect with their friends and family. (AP Photo/Eric Risberg) FILE - In this March 25, 2015 file photo, Mark Zuckerberg talks about the Messenger app during the Facebook F8 Developer Conference in San Francisco. For the first time, a billion people used Facebook in a single day on Monday, Aug. 24, 2015. Zuckerberg marked the occasion with a post on his Facebook page, saying that one out of seven people on Earth logged in to the social network to connect with their friends and family. (AP Photo/Eric Risberg)

By Associated Press August 27, 2015 1 min read

NEW YORK (AP) – For the first time, a billion people used Facebook in a single day on Monday.

CEO Mark Zuckerberg marked the occasion with a post on his Facebook page, saying that one out of seven people on Earth logged in to the social network to connect with their friends and family.

The 1 billion figure is different from the daily user numbers Facebook discloses each quarter when it reports its financial results. Those are the average number of daily users, counted over a 30-day period. Facebook had 968 million daily active users in June.

Overall, Facebook has nearly 1.5 billion users who log in at least once a month. It hit the 1 billion user milestone in October 2012. Most people on Facebook live outside the U.S. and Canada.