SAN JOSE, United States — EBay Inc forecast lower-than-expected revenue and profit for the current quarter and full year, as the e-commerce company struggles against a strong dollar and stiff competition from Amazon.com Inc.

The company which is also being hit as brick-and-mortar retailers such as Wal-Mart Stores Inc boost their online presence, reported that its revenue was flat in the crucial holiday quarter.

EBay's shares fell about 11 percent to $23.51 in extended trading on Wednesday.

The company forecast full-year adjusted profit of $1.82-$1.87 per share and revenue of $8.5 billion-$8.8 billion.

That was lower than analysts' average expectation of $1.98 per share in profit and $8.99 billion in revenue, according to Thomson Reuters I/B/E/S.

"It appears eBay is guiding to a decline in profit in 2016, which is very concerning," Gil Lurie, an analyst with Wedbush Securities, said.

EBay's forecast for first-quarter adjusted profit of 43-45 cents per share and revenue of $2.05 billion-$2.10 billion also missed analysts' average estimates.

The company's revenue was $2.32 billion in the fourth quarter ended Dec. 31, flat with a year earlier and in line with analysts' average expectations.

While the number of active buyers on eBay's platforms grew 5 percent, there was no growth in gross merchandise volume, or the total value of all goods sold on its sites.

Online sales in the United States jumped a better-than-expected 9 percent to $105 billion in the November-December holiday period, according to the National Retail Federation.

"While not a direct competitor in every respect, the growth of (Amazon's) successful Prime service has locked more customers into using its services and sites in a way that is unhelpful to eBay," said Carter Harrison, a retail analyst at research firm Conlumino.

San Jose, California-based eBay, which derives nearly 60 percent of its revenue from overseas, also faces headwinds from a strong dollar.

The average value of the dollar against a basket of currencies was 11.7 percent higher in the fourth quarter compared with the same quarter last year.

EBay's revenue grew 5 percent on a forex-neutral basis in the quarter. On the same basis, gross merchandise volume also rose 5 percent.

The company's net income fell to $477 million, or 39 cents per share, from $1.02 billion, or 82 cents per share.

By Sai Sachin R, Mari Saito; editor: Savio D'Souza.