’s website went down around 1 p.m. Pacific time today for as much as 45 minutes due to unknown causes.

The outage appears to have affected Amazon’s main website for all U.S. and Canadian visitors. VentureBeat was able to confirm that it was offline for at least 20 minutes, and the website Down For Everyone or Just Me also confirmed the outage for that time period.

Estimates differ on exactly how long Amazon was offline: Some reports have it at 15 minutes,  25 minutes, 40 minutes, and 45 minutes. At 40 minutes, the outage could have cost the company as much as $4.72 million in lost sales, the Puget Sound Business Journal estimated, based on the company’s average sales of $117,882 per minute. Of course, that’s an average rate, and sales at the online retailer might be expected to be much brisker on a Monday afternoon in the summer, when people are shirking work by ordering barbecue tools, Hawaiian shirts, boxes of cheap outdoor drink tumblers, or trashy novels to read on their Kindles.

Gigaom reports that Amazon’s country-specific websites were still online during the outage as were the websites of Amazon-owned companies like Zappos and

It’s very rare for Amazon’s homepage to go down, although the company’s cloud service, the Elastic Compute Cloud (EC2) went offline at least twice last year, once in June and once in October, taking out partner sites such as Netflix, Instagram, and Reddit.

Curiously, Google’s home page was offline for about five minutes August 16, potentially costing that company about $545,000 in ad revenue.

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