"We just passed an important milestone," chief executive and co-founder Mark Zuckerberg declared in a post on his Facebook page.
"On Monday, 1 in 7 people on Earth used Facebook to connect with their friends and family."
"When we talk about our financials, we use average numbers, but this is different," Zuckerberg added.
"This was the first time we reached this milestone, and it's just the beginning of connecting the whole world."
Zuckerberg also posted a video dedicated to the achievement.
In its earnings update last month, Facebook said monthly active users surged 13 percent from a year ago to 1.49 billion. The number of mobile active users rose to 1.31 billion.
We made this video to celebrate all you've done to help our community connect one billion people in a single day. It's an amazing milestone. I hope you enjoy.
Posted by Mark Zuckerberg on Thursday, 27 August 2015
Facebook on Thursday also said it is building new technology that video creators can use to guard against their works being copied at the social network without permission.
"This technology is tailored to our platform and will allow these creators to identify matches of their videos on Facebook across pages, profiles, groups, and geographies," a blog post said.
"Our matching tool will evaluate millions of video uploads quickly and accurately, and when matches are surfaced, publishers will be able to report them to us for removal."
Facebook planned to soon begin testing the new matching technology with a select group of partners, including media companies.
The California-based social network said that it has got word from some publishers that videos are sometimes uploaded to Facebook without permission in a practice referred to as "freebooting."
Facebook is already using an Audible Magic system that uses audio "fingerprinting" to identify and block copyrighted videos from making it onto the social network without proper authorization.
"We want creators to get credit for the videos that they own," Facebook said.
"To address this, we have been exploring ways to enhance our rights management tools to better empower creators to control how their videos are shared on Facebook."