BY Fast Company 2 MINUTE READ

While it’s too early to call Threads—Meta’s new microblogging platform—a bona fide “Twitter killer,” Mark Zuckerberg’s answer to Elon Musk’s flailing social network is off to a good start. Zuckerberg took to the new platform to announce that within the first four hours of its launch, five million users had already signed up to Threads. That number doubled to 10 million users just three hours later.

Ten million users in just seven hours is a pretty impressive feat, especially when you compare it to how long Facebook and Twitter took to get their first 10 million users. As Forbes notes, Facebook took 852 days to reach 10 million users while Twitter reached its first 10 million users in 780 days. Or, converting those numbers into hours, here’s how the three social networks stack up:

– 10 million Threads users: 7 hours

– 10 million Twitter users: 18,720 hours

– 10 million Facebook users: 20,448 hours

Answering a thread that asked whether anyone thinks Threads can become bigger than Twitter, Zuckerberg replied, “It’ll take some time, but I think there should be a public conversations app with 1 billion+ people on it. Twitter has had the opportunity to do this but hasn’t nailed it. Hopefully we will.”

Threads already has a separate app, but users must have an Instagram account to sign up.

Despite today being launch day for Threads, Zuckerberg also posted on Twitter for the first time in over 11 years. The post was a meme of two identical Spider-Men pointing at each other—a not-so-subtle dig that Threads is here to replace Twitter.

So far, Twitter owner Elon Musk hasn’t replied to Zuck’s posting on his social network, but in the weeks before Threads opened to the public the two tech CEOs agreed to a cage fight.

While Musk has yet to directly address today’s launch of Threads, the Twitter owner did reply to a tweet that posted a screenshot of a 2018 email in which Musk reveals he deleted his Instagram account. In his reply, Musk said, “It is infinitely preferable to be attacked by strangers on Twitter, than indulge in the false happiness of hide-the-pain Instagram”.

It seems like 10 million other people, so far, disagree.