Two years ago, Instagram was sitting pretty at 300 million monthly active users—an impressive milestone for such a young social network. But that pales in comparison to Instagram’s latest milestone. The Facebook-owned company on Thursday announced it has surpassed the 600 million monthly active user mark, doubling its tally from 2014.

Think about that. In just over two years, the company’s popularity has ballooned at an electric pace—and these are active users, not just a static metric that tallies a total all-time. 600 million people across the globe are actively posting, commenting, and liking photos on the platform every month. And the service is only getting bigger.

After launching in 2010, it took a little while for the service to catch on. But thanks to the rise of smartphones—and Instagram’s evolution as a service; it introduced a Snapchat-like feature this year called Stories—the platform’s growth has been unstoppable. In 2014, it took just seven months to double its monthly active user count, going from 200 million to 300 million.

What’s next for the platform?

It’s been impressive to see how Instagram has gone from simple photo-sharing service to social media powerhouse. The platform is no longer about slathering photos in filters; it’s now a community where people go to share vacation photos, food conquests and more.

Earlier this week, Instagram introduced a Pinterest-like feature that allows users to bookmark photos for later viewing, along with the ability to stream live video. It shouldn’t take long until the service crosses a billion active users a month.