David Karp, the CEO of New York-based Tumblr, revealed some fresh stats about the micro-blogging platform’s growth today. The company is seeing 20 billion pageviews a month, up from 15 billion at the beginning of the year, Karp said at GigaOm’s Roadmap conference in San Francisco today. That’s a growth rate of more than 30 percent per year. Compare that to 13 billion pageviews a month in September of last year, and a little over 4 billion pageviews a month in January 2011.
Karp said the site’s rapid growth has made the company think deeply about its identity as it adds more users that may be outside of its original base.
“It’s forced us to be very disciplined about who we’re building this for,” Karp said. “There are moments where we want everybody in the world using Tumblr. And then there are moments where we have to pull it down and remember that the reason anybody in the world even cares is because there’s a smaller community here that is making this incredible stuff.”
The company, which has raised a whopping $125 million in venture capital to date, is monetizing just a small piece of that network. They sell advertising against roughly 120 million impressions a day.
“We make some sliver of this attention available to advertisers,” Karp said. “The business model is not a particularly complicated one.” That advertising product, called Tumblr Radar, shows sponsored content from brands in a “Spotlight” area on the right-hand bar of the site.
Like all other social networks including Facebook and Twitter, Karp said the company has to maintain a fine balance between giving paid sponsors visual space, while not compromising the user experience or feel of the community.
“As far as how we keep it out of conflict with our mission of enabling creators around the world, what we do is treat advertisers in the same way as those creators,” he said. “There are no brand pages or promoted posts. The one difference advertisers have is that they’re able to write a check to elevate their stuff in this ecosystem.”
Karp said he originally started Tumblr as a product he wanted to use himself.
“I wanted an ease of expression where I could up put a video or photo and I wanted it to have my own domain name. I wanted it to be something that I was really proud of,” he said.
A interesting design and user experience decision they had to make several years ago was on how to incorporate commenting into Tumblr. After seeing online discussions on other sites dissolve into vitriol or obscenity, Karp and Tumblr’s staff came up with the idea for re-blogging.
“We really wracked our brains for a few months,” he said. “We needed some mechanism for feedback and this was 2007, where it had become so clear with sites like YouTube, that at some point, these networks get big enough… and you pass over into this world of Internet awfulness. If you look at the comments on YouTube, it’s a terrible place.”
He said Tumblr’s now classic re-blogging feature got around this issue by forcing users to own their own commentary in their online space.
“To add your commentary, you had to have your own soapbox over here,” he said. “You’re not allowed to show up, shout at me and tell me I’m a jerk. You have to take it with you.”
Tumblr is a re-envisioning of tumblelogging, a subset of blogging that uses quick, mixed-media posts. The service hopes to do for the tumblelog what services like LiveJournal and Blogger did for the blog. The difference is that its extreme simplicity will make luring users a far easier task than acquiring users for traditional weblogging. Anytime a user sees something interesting online, they can click a quick “Share on Tumblr” bookmarklet that then tumbles the snippet directly. The result is...