• Revenue in Amazon's online ad business rose 19% to $13.92 billion.
• Amazon has emerged as a force in digital advertising, trailing only Meta and Google in the U.S.

reported a 19% increase in online ad revenue in the first quarter, beating analysts' estimates.

Ad sales climbed to $13.92 billion, while analysts on average were expecting $13.74 billion, according to StreetAccount.

The numbers were contained in Amazon's The company reported total first-quarter sales of $155.67 billion, compared to Wall Street projections of $155.04 billion.

Although Amazon's online ad business represents a fraction of overall sales, it has emerged in recent years to become the third-biggest platform in the global digital advertising market, behind only and

Online advertising is a particular area of focus for investors due to economic uncertainty and increasing tensions between the U.S. and China over trade. While President Donald Trump's China tariffs will likely affect Amazon's core retail business, the company's online ad unit could also feel some pain.

So far, tech companies with online ad businesses have reported solid first-quarter earnings, but warned of potentially tougher times later in the year.

Meta reported stronger-than-expected this week, but said ad sales in the Asia-Pacific region came in at $8.22 billion for the quarter, trailing analysts' estimates of $8.42 billion.

The company's finance chief Susan Li that "Asia-based e-commerce exporters" have slowed their online ad spending likely due to the de minimis trade loophole .

When Alphabet reported last Thursday, it revealed that ad sales grew 8.5% year over year to $66.89 billion and YouTube ad revenue increased 10% to $8.93 billion. But Alphabet executives told analysts that it to its Asia-Pacific-focused advertising business.

on Tuesday said it had " to start the current quarter," which resulted in the company saying it would not provide guidance.

Last week, reported its latest quarterly earnings and said search and news advertising sales, minus payments to its affiliates, grew 15% year over year to $449 million.

also reported on Thursday that beat on sales and guidance. The company's first-quarter sales soared 61% year over year to $392 million.

Although Reddit's second-quarter guidance topped analysts' projections, CEO Steve Huffman said there is some economic shakiness.

"Ever-shifting macro environments like these create both challenges and opportunities," Huffman wrote in a letter to shareholders. "We've grown through challenging times before — people need connection and information just as much in uncertain times."

reports earnings on May 8.

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