Tumblr's porn ban has apparently resulted in a major online traffic decrease.

Traffic to Tumblr has fallen by close to 30 percent since December, when the blogging platform banned adult content, according to market intelligence firm SimilarWeb.

In December, Tumblr had an estimated 520 million visits, which dropped to 436 million in January and then 369 million in February, according to SimilarWeb's data.

The traffic numbers, which were first reported by TheNextWeb, are hardly a surprise. For years, Tumblr was a popular way for porn enthusiasts and erotic artists to share adult content. But in November, the platform had its iOS app yanked from the Apple App Store after child pornography was found on the site.

Not long after, Tumblr announced a ban on adult content beginning Dec. 17. However, the platform said it had been considering the change for months as a way to welcome more users.

"We spent considerable time weighing the pros and cons of expression in the community that includes adult content. In doing so, it became clear that without this content we have the opportunity to create a place where more people feel comfortable expressing themselves," Tumblr's CEO Jeff D'Onofrio said at the time.

However, the ban sparked an uproar among erotic artists and sex workers who had been promoting their projects on Tumblr. As a result, many had no choice but to leave the site and try other, lesser-known platforms, such as Mastodon and Pillowfort.

It didn't help that Tumblr's attempts to block adult content ensnared many legitimate blogs that were free of porn. To enforce the ban, the platform used computer algorithms that sometimes struggled to distinguish porn from pictures of dogs, Jesus, and superheroes.

In response to the reported traffic drop, a Tumblr spokesperson said: "We made a strategic decision for the business that better positions it for long-term growth among more types of users. This was the right decision."

A separate website ranking firm, Alexa, has also slightly downgraded Tumblr's website ranking since the porn ban. However, the blogging platform is still the 68th most visited website in the world, according to Alexa.

Editor's Note: This story has been updated with more context about Tumblr's decision to ban certain adult content.