California-based social-networking giant Facebook on Wednesday reported stronger-than-expected earnings for the second quarter of this year, thanks to a sharp increase in mobile ad revenues.

Revenues during the three months ended June 30 jumped 53 per cent year-on-year to $1.81 billion, while profit climbed to $331 million. In the corresponding three months of the previous year, the company had reported a loss of $157 million.

Mark Zuckerberg, founder and chief executive of Facebook, said, "The work we've done to make mobile the best Facebook experience is showing good results and provides us with a solid foundation for the future."

As per the revealed figures, 41 per cent of the company's total ad revenues were generated by mobile ads, considerably up from 30 per cent in the previous quarter. In the April to June quarter of 2012, the company generated virtually nothing from mobile ads.

As per industry tracker eMarketer's estimates, Facebook's share of the global digital ad market will likely jump to 5.04 per cent by the end of this year. The global digital ad market currently values nearly $117 billion.

After the announcement of the quarterly results on Wednesday, Facebook shares gained as much as 20 per cent to $31.75 apiece.