Shares of the company, which also raised its full-year profit and revenue forecasts, jumped 12 percent in extended trading on Thursday.
LinkedIn has been spending heavily on expansion by buying up companies, hiring sales personnel and increasing its presence in China and other markets outside the United States.
Expanded offerings helped boost revenue from the company's Talents Solutions business, which connects recruiters and job seekers, by 46 percent in the third quarter. The business accounted for nearly two-thirds of LinkedIn's total revenue.
Revenue from advertisements on its website rose 28 percent, while paid membership income increased 21 percent.
LinkedIn, which operates in over 200 countries and territories, said the total number of members rose 20 percent to 396 million at the end of the third quarter.
The company said the number of its subscribers in China had more than tripled since early 2014, when it launched a local language version, to over 13 million currently.
LinkedIn also said 55 percent of its traffic was through mobile devices such as smartphones and tablets.
The company raised its 2015 revenue forecast to $2.975 billion-$2.980 billion from $2.94 billion, and adjusted profit forecast to about $2.63 per share from about $2.19.
The net loss attributable to shareholders widened to $40.5 million, or 31 cents per share, in the quarter ended September 30 as costs surged 46 percent.
Excluding items, LinkedIn earned 78 cents per share, topping the average analyst estimate of 46 cents, according to Thomson Reuters I/B/E/S.
Revenue rose 37.2 percent to $779.6 million, beating analysts' expectations of $755.8 million, partly due to the acquisition of training video company lynda.com in May.
LinkedIn shares were trading at $243.27 after the bell.
Up to Thursday's close, the stock had risen about 31 percent from its year-low of $165.57 hit on August 24.
© Thomson Reuters 2015
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