Facebook shares surged more than 12 per cent in after-hours trading after the social media company more than doubled its profits in its fourth quarter.
Faster than expected advertising growth, particularly in mobile, was behind the performance.
Net income was up at $1.56 billion (£1.09 billion) in the three months to December 31, versus £701 million a year earlier.
Revenue was up by 52 per cent at $5.84 billion.
The figures show Facebook has been able to withstand the recent economic turmoil and the strengthening US dollar, both of which have hit other tech firms like Apple and eBay.
Facebook said mobile ads accounted for 80 per cent of its advertising revenue in the fourth quarter, compared with about 78 per cent in the third quarter and 69 per cent a year earlier.
“It's much stronger ad growth than we were expecting,” said Ken Sena, an analyst at Evercore ISI.
Its mobile strength helped offset concerns about Facebook's big bets on other services like Whatsapp and virtual reality, divisions that are yet to turn a profit.
Slower growth in operating expenses also pleased shareholders.
The company's shares were $11.45 higher at $105.90 at the end of extended-hours trading
Additional reporting by Reuters
