Photo

If you spend any measurable amount of time on the Internet, you’ve likely visited — or at least looked at — an image hosted on Imgur (pronounced “image-er”).

The photo-sharing service is extremely popular; each month, the site draws 130 million unique viewers who click on nearly five billion different images and pages. Each day, 1.5 million images are uploaded to the site, and 1.3 billion images are viewed.

But despite that reach, the company is known for being an extremely small and extremely lean bootstrapped service, led by a founder who likes to say that the only financial investment he’s ever made in the company was the $7 he spent to register the domain name.

That’s about to change.

On Thursday the company announced that it raised $40 million from Andreessen Horowitz in a Series A round of funding.

“Being bootstrapped is great,” said Alan Schaaf, the founder and chief executive. “You own 100 percent of it. But the downside is that you aren’t able to move as fast as you want.”

Imgur was introduced in 2009, and has managed to stay in business and cross into profitability by employing a small team and working with advertisers to support the site. Mr. Scaaf said that he had been reluctant to raise money over the last five years, but felt that the site’s growth and audience required him to expand the company.

“We’ve talked with over a dozen VCs and angel investors over the years,” he said. “But we’ve never clicked with any of them until Andreessen. During our initial meeting, we were bouncing ideas around about where Imgur could go.” That persuaded him to work with the firm.

Imgur’s first priority will be to hire more engineers and salespeople and move into a larger office, Mr. Schaaf said, and to start building new applications to enhance the service’s mobile experience. The company also recently hired Tim Hwang, who founded ROFLCon, a conference about Internet culture and memes, among other things; he will work on special projects like real-world events for Imgur users and partnerships with other Internet companies.

Part of Imgur’s popularity comes from its convenience. The site does not require its users to register to upload images to the service, and it works for browsing funny photos as well as it does for people who just want a simple way to quickly post an image.

Photo

Reddit, the popular community news site, also invested a small amount of money. Reddit was instrumental in bolstering the site’s early traction, as Mr. Schaaf initially created Imgur as a tool for uploading images to Reddit. From there, it began to become more of a community itself, as people began leaving comments on images or turning them into memes. The average user spends around 11 minutes — the equivalent of three YouTube videos — on the site, the company said.

Lars Dalgaard, the general partner at Andreessen Horowitz who led the funding round, said the firm had been interested in giving money to Imgur for years. But Imgur resisted until last summer, when its executives agreed to a meeting.

Mr. Dalgaard said that he and his firm were impressed by the company’s traffic and growth figures, and that he sees it as a kind of future-forward looking media and entertainment company.

“Everyone snacks on information,” he said. “People in a meeting or on the elevator who don’t have time to watch a video or get their book back open, but still want something meaningful.”