During a recent event at Pinterest’s headquarters in San Francisco, CEO Ben Silbermann revealed the service now plays host to more than 30 billion pins. It’s an impressive figure that looks even more promising when you learn that nearly 50 percent of those pins took place within the past six months.

Since the site’s inception just over four years ago, users have additionally created more than 750 million boards. The rapid growth now means the company is ranked among the elite social media sites in the world, but how exactly did it happen so quickly?

As TechCrunch points out, a large portion of the site’s recent success stems from a feature called related pins that was introduced late last year. As the name suggests, related pins will recommend other pins that are similar in nature to stuff you’ve already been collecting. Pinterest claims over 90 percent of pins now have related pins attached while an additional 20 percent of people are repinning related pins.

Other recently added features that have no doubt helped expand Pinterest’s reach include alerting users when the price of a pinned item goes down, browser tracking for personalized pins and a revamped mobile site that caters to international users.

As other companies have noted, the mobile push is definitely paying off for Pinterest. Last month, the company revealed that 75 percent of all traffic originated from native mobile apps.