Who’s winning the race in social media? Monthly active users by the numbers [Chart]

Instagram(s fb) announced Thursday that it’s hit 90 million monthly active users, finally releasing the metric that most people look to in evaluating the reach of a particular website or app. Monthly active users are one of the better indicators of a company’s true reach — you can have millions of users, but if they never log in and use your service, that doesn’t mean much.
We broke down the numbers for all of the prominent social media services that have released a monthly active user stat, and then plotted those numbers along with the years since the company launched. The area of the circles is representative of the service’s monthly active users. And you might find some of the results surprising. For all we talk about Twitter, it is only a fifth the size of Facebook. And while LinkedIn(s lnkd) was the first company founded of all we charted, it still has pretty tiny numbers.
Pinterest declined to release numbers, although it did make it on comScore’s list of top 50 web properties in September. With Google+ numbers, it’s good to remember that the service is so deeply integrated into other Google products, it can be more difficult to understand exactly how people are using the platform.
But taking a look at the numbers we do have — and it’s worth noting that the majority of major sites do release the monthly active figure — gives you a good sense of where traffic and user interest is going. And if your users aren’t interested in visiting your site or app each month, that’s probably not a great sign:
[protected-iframe id=”72c7885aaac6e51c550a045278781524-14960843-25766478″ info=”http://infogr.am/Social-media-by-users-and-age” width=”550″ height=”596″ frameborder=”0″ style=”border:none;” scrolling=”no”]

Charts by Rani Molla/GigaOM