You may not be using Google+, but your friends probably are.If they’re not hanging out and posting photos of cute puppies and sunsets, there’s a good chance they’re using Google+ to log in to various web sites — and
 increasingly, they’re also clicking the +1 button to share those sites. In fact, it’s the clear number two social network according to a variety of measurements.
A new study commissioned by Janrain shows that, of the people who use social networks to log in to other websites, almost half (46 percent) use Facebook. But Google+ is in a strong second place, with 34 percent of social logins. (Janrain makes tools to help web developers use social network logins on their sites.)
That bolsters the claim that Google+, despite its late start, is solidifying its position as the number 2 social network after Facebook.
In a distant third place: Yahoo, with just 7 percent of social logins; and Twitter, with 6 percent.
Google+ launched to a limited number of users in June, 2011, and more widely in September of that year. In the two years since then, it has zoomed past social networks that were years ahead and had hundreds of millions of users already: LinkedIn, Twitter, and a handful of Chinese social networks.
Google+ now has more than 500 million registered users and 343 million active users, according to an independent study by GlobalWebIndex from December, 2012.
Facebook is twice as big, claiming over a billion registered users, while GlobalWebIndex estimates Facebook has almost 700 million active
But Google+ is growing faster, according to some measurements. It’s holding steady on social logins, according to Janrain’s data, growing just a fraction of a percent in Q2 2013. (Facebook sharing also stayed at roughly the same level — see the graph above.)
But sharing on both networks is increasing rapidly — only it’s growing much faster on Google+. People who use Facebook are sharing 10 percent more each month, in aggregate, while Google+ shares (aka +1s) are growing by 19 percent per month, according to a recent estimate by Searchmetrics, which tracks social network data.
At that rate, Searchmetrics estimated, Google will surpass Facebook by May 2016, at which time its users will generate over 1,096 billion +1s per month (yes, more than a trillion) while Facebook users will generate just 849 billion shares per month.
However you look at it — registered users, active users, social logins, or shares — Google+ is a surprisingly serious second. And it may even be a contender for the #1 spot in a few years.
Now if I could only find some people to hang out with on Google+.