Google's online social networking service 'Google Plus' has crossed 90 million users mark since its launch in June.

Google Plus now has attracted 90 million users, reflecting the huge interest in the social networking site which was opened to the public on September 20. That more than doubles the 40 million that Google reported in October.

Earlier, Google Plus service was available only through invitation as part of trial runs.

Interestingly, rival Facebook took about four years to reach 90 million users. Facebook, founded in 2004, has now 800 million users globally.

"I am super excited about the growth of ... Google Plus, which now has 90 million users globally – wellover double what I announced just three months ago. By building a meaningful relationship with our users through Google Plus we will create amazing experiences across our services," Google CEO Larry Page said while announcing the company's latest quarterly earnings.

Google unveiled 'Google Plus' in late June as part of efforts to garner a share of the lucrative social networking space that has so far been dominated by Mark Zuckerberg—led Facebook.

Since launch, Google has added toolbars and other buttons on its websites to aggressively promote the service.

During the quarter, Google has reported a net income to $2.71 billion in for October-December, which analysts termed as below market expectation.

It registered revenue of $10.58 billion for the quarter ended December 31, 2011, an increase of 25 per cent from the year-ago period.