A billion people now use Facebook Messenger every month, the company announced Wednesday.
The company's stock hit an all-time intraday high on Wednesday, up more than 1 percent at $121.92.
Facebook commemorated its massive Messenger audience, which has approached the size of the world's largest countries, with a celebratory balloon emoji, calling Messenger "one of only a handful of apps worldwide that touch so many lives."
Messenger has built on the social network's widespread influence. For instance, 14.6 million people in the U.S. generated 52.4 million likes, posts, comments and shares related to the GOP convention overnight, Facebook said.
It comes as social media companies such as Snapchat increasingly move toward messaging, one of the most popular forms of communication abroad. Even before the milestone, Facebook Messenger was the top-used messaging app worldwide, followed by WhatsApp, Skype and Line, according to data collected by eMarketer.
Facebook has been using its sizable pull to build out its Messenger platform, adding features like payments, ride sharing, a digital assistant and thousands of bots, automated apps within Messenger.