New figures from comScore show that Facebook recorded 87.7 million unique US visitors during July, a 14% lead on social networking giant Twitter which only recorded 21.2 million unique visitors.
The figures show that Facebook is growing four times faster than its rival, even as its membership base is more than four times as big.
Facebook is now the fifth largest web entity in the US, passing Fox Interactive Media, (which includes MySpace.com), and is now the fourth largest site in the world. However, Twitter beats Facebook on the global scale with 44.5 million unique visitors worldwide during June.
Tech blog TechCrunch points to the "Everyone Button" as the reason for the site's growth.
"Facebook members who didn't have public profiles (i.e. most people) all of a sudden had the option to share items in their stream with everyone else on Facebook, and they could decide to do this on an item-by-item basis," it said.
"The more items that are shared publicly, the more people who can see them. I believe this is what happened (and have asked Facebook for confirmation). Not only did this drive more people to Facebook, but it also increased the time spent on the site by a whopping 36% in June versus July."
