NEW YORK - Facebook said Thursday that it now has more than a billion users, in a new milestone for the world's biggest social network.
Co-founder and chief executive Mark Zuckerberg made the announcement, saying the number is "humbling."
"This morning, there are more than one billion people using Facebook actively each month," he said in a statement.
"If you're reading this: thank you for giving me and my little team the honor of serving you. Helping a billion people connect is amazing, humbling and by far the thing I am most proud of in my life."
Interviewed on the NBC Today show, he called the number a major achievement.
"To be able to come into work every day and build things that help a billion people stay connected with the people they care about every month, that's just unbelievable," Zuckerberg said.
Facebook said it reached one billion monthly active users on September 14 at 12:45 pm Pacific time. That includes 600 million mobile users.
In its last update in June, Facebook said it had 955 million users including 543 million using mobile devices.
The California company launched a public offering in May, but has seen its share price tumble amid concerns that it may not be able to grow revenues as users migrate to mobile devices.
Facebook shares, which hit the market at $38 in May, closed Wednesday at $21.83, but in pre-market trade was up 1.9 percent at $22.25.
In the NBC interview, Zuckerberg said the company was moving forward despite some rough patches.
"Things go in cycles. We're obviously in a tough cycle now and that doesn't help morale, but at the same time, you know, people here are focused on the things that they're building," he said.
"I mean, you get to build things here that touch a billion people, which is just not something that you can say at almost anywhere else, so I think that's really the thing that motivates people."
Since Facebook's launch, users have produced over 1.13 trillion "likes," some 140 billion friend connections and have uploaded 219 billion photos.
The social network has also seen 17 billion location-tagged posts, including check-ins, and 62.6 million songs which have been played 22 billion times.
The median age of the user is around 22, according to Facebook.
According to the independent website Social Bakers, the largest number of Facebook users are in the United States, over 166 million, followed by Brazil (58 million), India (55 million), Indonesia (47 million) and Mexico (38 million).
Zuckerberg, in an interview with Bloomberg Businessweek released Thursday, said the company was taking the new milestone in stride.
"We don't want to overly celebrate any particular milestone, so what we do is we have hackathons," he said.
"So people will be thinking of ideas and working on prototypes and things that we'll need to do to help connect the next billion people, which I think is pretty cool."