Business networking site LinkedIn has reported a 120% rise in revenues between April and June in its first results as a publicly-traded company.
Revenues hit $121m (£74m). Net profit rose to $4.5m from $4.3m a year ago.
In May, LinkedIn became the first major social networking site to go public, looking to cash in on investor appetite for social media firms.
But many analysts say that after the dotcom boom of a decade ago, we have now entered a social media tech bubble.
LinkedIn priced its shares at $45 in May, but the share price more than doubled on its first day of trading.
A $100 share price values the company at about $10bn, although the price has fallen to about $95 a share since then.
The LinkedIn website allows users to create professional profiles online and share them with others.
Ken Sena, analyst at Evercore Partners, said that the company's numbers for the April to June period had to be good to support the "lofty valuation".
Its membership base increased 61% on the same quarter last year to 115.8 million.
Chief executive Jeff Weiner said in a conference call that the site was adding about two members every second, and that it had more than 120 million members as of Thursday.
LinkedIn's profit was a much better result than expected, with most analysts forecasting a loss in the quarter.
The company itself has warned that it will not be profitable in 2011 as a whole, as it seeks to expand by investing aggressively.