Since launching in May, Google Photos has become one of the industry’s most reliable and beloved storage solutions, offering a “set it and forget it” usability that has ballooned the service’s popularity. And, according to numbers released by Google, it’s even more popular then anybody could have predicted.

After just five months of availability, monthly active users have grown to more than 100 million, which is an astounding figure. It took Instagram two and a half years to reach that number, while services such as Twitter and Pinterest took around five years to reach that milestone. And with some big new features hitting Google Photos this winter, usage numbers are only going to grow.

What appeals to people most about Google Photos is how easy it is to use. Just sign in with your Google account, set up automatic photo uploads, and you’re good to go. We did an extensive hands-on with the service earlier this year, and even shortly after launch it was easy to see why people love Google Photos. What’s most impressive is that Google Photos has hit these numbers even with many other storage solutions already on the market.

If you haven’t yet signed up, Google Photos provides users with unlimited high quality storage. You can also upload full resolution versions, though that will count against your storage quota, so you’ll have be less cavalier with what you upload.

In addition to the impressive number of monthly users, Google said that Photos has freed up 3,720 terabytes of storage on user phones thanks to features like automatic uploads. That’s something I rely on every day, so I can attest to how useful it is when trying to free up space.

Check out our hands-on of the service below.