SAN FRANCISCO • Facebook said that 2 billion people are regularly using its flagship service, marching past another milestone in its growth from a college curiosity in the United States to the world's largest social media network.
Chief executive Mark Zuckerberg disclosed the number to his followers in a Facebook post.
"It's an honour to be on this journey with you," he wrote on Tuesday.
The user base is bigger than the population of any single country, and of six of the seven continents. It represents more than a quarter of the world's 7.5 billion people.
Facebook defines a monthly active user as a registered Facebook user who logged in and visited Facebook through its website or a mobile device, or used its Messenger app, in the past 30 days. It does not include people who use the Instagram or WhatsApp networks but not Facebook.
The company last month said duplicate accounts, according to an estimate from last year, may have represented some 6 per cent of its worldwide user base.
The social network's user population dwarfs that of similar companies. Twitter reported in April monthly active users of 328 million, while Snap's Snapchat had 166 million daily users at the end of the first quarter.
WeChat, a unit of Tencent Holdings and a widely used service in China, said in May that it had 938 million monthly active users in the first quarter.
Facebook had 1.94 billion people using its service monthly as of March 31, up 17 per cent from a year earlier. It reached 1 billion in October 2012.
Facebook's growth has increasingly come from outside the US, Canada and Europe. Three years ago, those regions accounted for some 38 per cent of users, against about 30 per cent in the first quarter this year. To boost penetration rates in developing nations, it has rolled out pared-down versions of its apps that use less data, and it has been developing solar-powered drones to extend Internet connectivity worldwide.