Amazon.com revenue grew more than expected for the first quarter, largely offset by a sharp increase in spending on technology, content and new warehouses as the e-commerce company branches into new businesses.
Amazon's international unit, which accounts for 40 percent of sales, continued to be a drag as sales growth slowed to 18 percent during the quarter. Global unit sales, a closely watched measure of how many items Amazon has sold, also decelerated, rising only 23 percent.
The company is investing heavily in new markets abroad, particularly China, where it faces tough competition with Chinese e-commerce company Alibaba.
"A lot of the things that we've done—making sure that we have the right pricing in place on behalf of the customers, making sure that our service levels are where we need them to be—those are the things we continue to work on in China," Chief Financial Officer Tom Szkutak said during a conference call.
"Is it a large investment? Yes, it is. And that investment has increased over the past several years."
Shares climbed in extended-hours trading. (Click here to get the latest quotes.) The stock rallied nearly 4 percent in the regular session ahead of the earnings report.