Clear Channel announced today that its popular free digital radio app, iHeartRadio, has amassed 10 million registered users in a mere 8 months since it started inviting people to sign up for accounts. While that sounds like a meteoric gain all by itself, let’s put that into perspective: iHeartRadio reached that milestone quicker than Facebook, Pandora, Spotify, and Instagram attained that number.

While 10 million users is impressive, that’s likely a low estimate of the total amount of people who’re using the app since registration isn’t mandatory to use kick out the jams on iHeartRadio. People only need register if they want access to the Custom Station feature. Even without enabling the Custom Station feature, though, users can still access any one of the 850 radio stations in the United States that stream commercial-free over the service.

Brian Lakamp, Clear Channel’s Digital Media President, described the iHeartRadio’s registration growth as “mind-blowing” in a statement. “We’ve been able to drive this adoption like no other company could,” he said.

iHeartRadio’s off to a stampeding start but it’s still got a ways to go to catch up with some of its competitors. Pandora, for instance, celebrated 150 million users last week with some convincing evidence that the internet radio service will likely continue to expand over the year.

Then again, iHeartRadio’s offering a different service than Pandora so there’s not really much keeping both radio providers from sharing listeners. The internet radio market is swelling as of late and that’s largely without the help of social media to promote it.

Clear Channel Chairman and CEO John Hogan concurs that iHeartRadio’s success reinforces the trend that audiences are turning up that sweet internet sound. “This is a reflection on how consumers are embracing digital as one more way to use our broadcast brands,” he said. He added that Clear Channel plans to continue developing the iHeartRadio platform so as to expand its fan base.

Currently, anybody who can’t stand the silence can tune in to iHeartRadio via the website or download the mobile app for iPhone, iPad, Android, Windows 7, and Blackberry.

“We take being a multiplatform company seriously,” Hogan concluded.