Google Inc. is adding 625,000 new users a day to the Google+ social-networking service, which may total 400 million members by the end of next year, according to independent analysis of its growth.
The site’s popularity has accelerated in recent weeks, with almost a quarter of its total user base joining in December alone, said Paul B. Allen, the founder of Ancestry.com Inc., who tracks the numbers as Google+’s “unofficial statistician.”
Google, the world’s largest Internet-search company, aims to challenge the social-networking supremacy of Facebook Inc., a site with more than 800 million members. Google+, which lets users organize their friends in circles, was introduced earlier this year as a test project and then opened up to the general public in September.
Google+ may be benefiting from the popularity of Google’s Android mobile operating system, which makes it easy to sign up. As the service gains traction, more people will invite family and friends to join, further accelerating its growth, Allen said in a Google+ posting. He works at FamilyLink.com, a company he helped start in 2006 with other Ancestry.com co-founders.