With 300M users, Instagram is now bigger than Twitter

Instagram has hit a major milestone. The company now has more than 300 million monthly active users, sharing more than 70 million photos every day, and an average of 2.5 billion daily "likes."

That 300 million number is meaningful for a couple of reasons.

First, it's impressive growth. Since March, the number of new monthly active users has totaled more than 100 million.

Second, this now makes the photo-sharing app, which Facebook bought for $1 billion in April 2012, bigger than Twitter, which has 284 million monthly active users, and whose market cap is around $23 billion.

More than 70 percent of its users are outside the U.S., and users have shared more than 30 billion photos.

"We're seeing a lot of people coming in the fashion world, a lot of people coming in, in the youthful teens world, and a lot of people internationally as well," CEO Kevin Systrom said in an exclusive interview with CNBC.

Can Instagram keep up that pace of growth? "That's the big challenge for me and my team going forward," he said.

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One way Systrom aims to do that is to make it easier for people to discover content and find people to follow. "There are photos pouring in from everywhere in the world. If you're interested in really eclectic topics, I guarantee you there are accounts that are related to that. So we need to make sure to connect you with the content that matters most to you."

The 300 million marker isn't Instagram's only announcement Wednesday. As part of an effort to eliminate spam, it's announcing verified badges for celebrities, athletes and brands to help people ensure they're connecting with authentic accounts. The company says it's also working to deactivate spammy accounts to improve the user experience

Instagram co-founder Kevin Systrom.
Emmanuel Dunand | AFP | Getty Images
Instagram co-founder Kevin Systrom.

Eliminating spam is becoming increasingly important as Instagram ramps up its advertising business. Systrom said the company isn't competing against other tech companies, but rather against print and TV ads.

"We are selling brand advertising that shifts perceptions, for instance like Chobani," said Systrom.

"Chobani did a really wonderful yogurt campaign on Instagram to shift perceptions away from the fact that they were just yogurt. And they had a 7 point incremental lift on shifting that perception through a brand advertisement on Instagram. That's the type of thing you typically see in a magazine or on TV. If you look at those markets, they are very, very large. And I think that's what we're going after. So you can see where we're headed."

Systrom said it's possible that in the future he'll explore ways to make money outside advertising—mentioning brands' request to do premium filters. He said they've been cautious, but he won't count it out.

As for Instagram surpassing Twitter's user size, but still having a long way to go before catching up to its revenue—which was more than $360 million last quarter—Systrom demurred. "I think it's hard to compare Twitter and Instagram," he said. "Twitter has a more mature business. They're public. We've just started monetizing. We have a lot to prove before we're, you know, worth many billions of dollars,"

Did Systrom leave billions of dollars on the table by selling to Facebook when he did? Systrom said he doesn't think about it that way, and that he has Facebook to thank for a lot of his company's growth.

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