Facebook reported quarterly earnings that beat analysts' estimates on Wednesday, and revenue that topped expectations, as ad revenue grew 53 percent.
The fourth-quarter earnings were up from 79 cents per share on $5.84 billion in revenue in the year-earlier period.
Facebook shares rose as much as 3 percent after hours, but were last up less than 1.5 percent.
The company's ad business zoomed higher, as retailers poured money into snagging customers during the busy holiday shopping season. Only Google rivals Facebook when it comes to digital advertising dominance.
"That's just massive earnings growth," Danielle Hughes, CEO of Facebook-shareholder Divine Capital, told CNBC's "Closing Bell" on Wednesday. "Same thing for EPS."
But at the same time, Facebook's virtual reality company, Oculus, is on the hook for $500 million after losing a key lawsuit.
The results come after a volatile year for Mark Zuckerberg's social network, which despite its gargantuan size, has managed to add more users at a rapid clip. The company added 17 percent more monthly users from a year ago, and 18 percent more daily users.
"I think the real attractive thing about Facebook is it's got a multi-layer revenue growth story," Michael Graham, managing director and senior equity analyst at Canaccord Genuity, told CNBC's "Closing Bell." "Users are growing, engagement is improving and monetization of each user is also improving."
"Our business did well in 2016, but we have a lot of work ahead to help bring people together," Zuckerberg said in a statement.
Ad revenue exploded in the first half of the year, crushing estimates, as Facebook surpassed a billion monthly users on many of its major platforms, including mobile-only Facebook, Messenger and WhatsApp. Then in November, shares tumbled from their all-time high after executives warned that the number of new ads on the sites could "come down meaningfully" after mid-2017, and revenue growth could decline in the fourth quarter.
With messaging competitor Snap expected to file for a public offering soon, Facebook's video ambitions and daily engagement are in the spotlight. Facebook has announced plans to invest in original and licensed video and to add ads in between its live streamed content. The company added new advertising options on Instagram, especially on its Snapchat-like product.
Snapchat's augmented reality filters and "lenses" will be a key area of innovation as both companies compete, Hughes said.
"I think it shows the foresight and the long haul that Facebook has with [virtual reality technology] and how they believe it will take over the market," Hughes told CNBC. "People will eventually use this technology in everyday use, like we do with mobile [...] This will become the new mobile."
Facebook now has 1.146 billion daily mobile active users.
The company also has faced criticism for errors in some of its key advertising metrics, and for a plan that allows Zuckerberg to to give away 99 percent of his shares but "remain involved with Facebook in a leadership role."
This is developing news. Please check back for updates.
— CNBC's Michelle Castillo and Mack Hogan contributed to this report.
Correction: Facebook had 1.86 billion monthly active users in the fourth quarter of 2016. This story has been updated to reflect the correct number of monthly active users Facebook reported in the quarter.
Disclosure: Cannaccord Genuity makes a market in shares of Facebook and intends to seek or expect to receive compensation for investment banking services from Facebook