Amazon.com Inc. posted its second straight quarter of record profitability, but its recent string of blistering revenue growth is cooling. The company’s slower-growing Whole Foods Market business has weighed down gains, and its cloud-computing business faces stiffer competition.
The Seattle-based company on Thursday posted a profit of $2.88 billion—about 11 times last year’s figure—extending its profitability streak to more than three years. The company tamed some costs, including head count and shipping expenses, the latter...