Skype has 560 million registered, more than social networking site Facebook, according to the company's chief technology strategist.
Jonathan Rosenberg told the eComm conference in San Francisco that the company added 39 million registered users during the fourth quarter of the year, GigaOMreported.
By comparison, Facebook reached 400 million users in February.
Skype users made 36.1 billion minutes Skype-to-Skype calls during the quarter, up from 27.7 billion the previous quarter, and have made more than 250 billion minutes since launch.
The company accounted for 13% of international calling minutes in 2009, compared to 8% in 2008.
In an indication that the company's video calling ambitions are paying off, 36% of all Skype-to-Skype calls for the quarter included video.
Last month, 23 million users were logged into Skype at peak times, Rosenberg added.