ComScore revealed that Google reached the billion visitor milestone in May. It is the first time an internet company has hit this number.
Trailing after Google was Microsoft, with 905 million unique visitors, and Facebook with attracted 714 million users last month.
Yahoo was pushed into fourth place with 689 million unique visitors.
Microsoft in second place with 905 million visitors
Facebook grows by 30% to 714 million users
The rise of Google continues unabated as it emerged today that more than a billion visitors used its websites in May.
It marks the first time an internet company has hit the landmark figure, according to ComScore, a company which compiles web data.
The second most popular destination was Microsoft, with 905million unique visitors, and third was Facebook, which has grown by 30 per cent in the past year, attracting 714million visitors in the month.
Both Gmail and Youtube, which are part of Google, helped the company break the billion mark. Despite Google's staggering number of visitors, users spent more time on Facebook - a total of 250 billion minutes in May compared to Google's 200 billion minutes.