Amazon is increasingly going global, and it's taking sellers along for the ride.

In its first-quarter earnings report on Thursday, Amazon said that global sellers accounted for 25 percent of third-party sales on the site last year. That's growth of 50 percent from the previous year.

Amazon has been rolling out services to make it easier for merchants to become exporters using the company's logistics system and its vast network of fulfillment centers.

The more Amazon can lean on third-party sellers, the better for its bottom line. Rather than subsisting on the razor-thin margins that come with buying inventory in bulk from other brands and reselling it, the marketplace lets Amazon make money from fees that it charges for storing and shipping goods and fulfilling orders.

Growing Marketplace sales is one reason why Amazon's operating income surged 92 percent in the quarter, increasing more than twice as much as revenue, which rose 43 percent. Revenue from third-party seller services, which includes commissions, fulfillment and shipping fees, increased 44 percent to $9.3 billion, accounting for 18 percent of total sales.

Amazon shares jumped more than 6 percent in extended trading on Thursday after its results topped analysts' estimates.