Amazon reported earnings for the second quarter on Thursday.

Amazon reported earnings for the second quarter on Thursday. Matthias Balk/picture alliance via Getty Images

Amazon reported earnings for the second quarter on Thursday. Matthias Balk/picture alliance via Getty Images

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Amazon's AI bets are starting to worry investors.

While the tech giant beat analyst expectations for the second quarter, it gave weak profit guidance and vague answers about its competitive advantage in AI, sending the company's shares tumbling 7% in after-hours trading Thursday.

Net sales at Amazon grew 13% to $167.7 billion for the quarter ended June 30, above the $162 billion analysts polled by Bloomberg had expected. The company's earnings of $1.68 per share smashed estimates of $1.33.

But Amazon said its operating income for the third quarter would be between $15.5 billion and $20.5 billion, potentially lower than analysts' estimate of $19.41 billion, souring the mood.

During the company's earnings call, CEO Andy Jassy gave a broad and lengthy response to a question about how Amazon is responding to AI competition. The answer failed to express his personal views on his company's competitive advantage, but expressed his optimism in AI adoption.

Shares of the Seattle-based company sank 7% in after-hours trading on Thursday.

Executives also fielded questions about tariffs during the call.

Jassy said the company hasn't seen much effect in the first half of 2025 and pointed to the company's strong Prime Day results as evidence that shoppers are still placing orders despite the threat of tariff costs.