The selloff in Netflix stock is an opportunity, analyst Mark Mahaney said Thursday.

Shares of Netflix opened down more than 20 percent a day after the video-streaming company fell short of reaching its projected 50 million subscribers.

"They missed domestic streaming net adds by 26 percent, and the stock corrects by 26 percent, so I get the logic," he said. "I just want to remind people to step back a little bit. We like this entry point. We're buyers here."

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On CNBC's "Halftime Report," Mahaney of RBC Capital Markets explained why he remained bullish on the stock.

"We still think they get to 50 million subs by 2017. We think there's still $40 in earnings power in this name long-term," he said. "We like this stock right here, right now."

Mahaney has an "outperform" rating on the stock and a $550-per-share price target.

"If you think the subs are going to decline from here going forward, you don't buy the stock. If you think they can't get close to 50 million subs within two or three years, you don't buy the stock," he said. "We think they can. We don't think there's any dramatically new, nothing new, on the competitive horizon. And we think the package, the offering, from Netflix each year gets better and better for consumers, and more consumers will sign up for it. And you still have major secular trends behind the company."

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Mahaney said Netflix would benefit from the increasing adoption of tablets, as well as Internet-connected TVs. He also added the company's expansion into Canada resulted in similar profitability to its U.S. business, a point that bodes well for further international moves.

"Now they can slow the profitability ramp, but it'll still rise. And they've got more firepower with which to buy more content, to beget more subs," he said. "The flywheel still works here."

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Mahaney also downgraded eBay to "market perform," lowering his price target from $62 to $55 per share.

Amazon.com, he added, was "a contrarian buy for us."

"We stick with it, especially at $300," he said. "Love this entry point."

Disclosure: RBC Capital Markets is currently providing eBay, Inc. with non-securities services.