Costco shopper AP Photo/Rick Bowmer

Costco’s website crashed for several hours on Thanksgiving Day, which meant that customers were unable to shop its deals online and on its app.

According to the retail aggregate LovetheSales.com, this could have cost the retailer nearly $11 million in sales. This number was determined by analyzing the number of hours that the site was down and the amount of money Costco pulls in each minute in online sales.

A spokesperson for Costco did not immediately return Business Insider’s request for comment.

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Costco’s website crashed for several hours on Thanksgiving, and experts estimated that it could have cost the retailer as much as $11 million in sales.

According to data from the outage-tracking website Downdetector, which was shared with Business Insider by the retail aggregate LovetheSales.com, the website was down for at least 16.5 hours. A spokesperson for LovetheSales.com said that while some people may have been able to make purchases during this time, it would have been very minimal because of the number of problems with the site.

LovetheSales.com worked out that Costco would pull in about $11,035 in e-commerce sales per minute. A spokesperson said that this number was pulled from Costco’s end-of-year financials and adjusted to account for the busier period. This means that in this 16.5-hour time period, Costco could have missed out on as much as $10.9 million worth of sales.

A spokesperson for Costco did not immediately return Business Insider’s request for comment.

Several shoppers complained on Twitter about the outages throughout the day on Thursday:

Tweet Embed:

//twitter.com/mims/statuses/1200294275206000640?ref_src=twsrc%5Etfw

@costco site and app are down.#BlackFriday pic.twitter.com/jrUQn1eMJs Tweet Embed:

//twitter.com/mims/statuses/1200177832216936450?ref_src=twsrc%5Etfw

Dear @costco, your site being down is one thing. But to send me emails saying I forgot an item in my cart???? Icing on the cake. #CostcoWebsiteDown #Costco Tweet Embed:

//twitter.com/mims/statuses/1200176857821437952?ref_src=twsrc%5Etfw

*gets @Costco membership*

*Can’t shop at Costco cause the entire site has essentially been down all day*

Around midmorning ET on Thursday, Costco added a banner to its website alerting its online shoppers that the site was „experiencing slow response times.“

This was later updated. It now reads: „The website is currently experiencing longer than normal response times. Please note that all Thanksgiving Day-only promotions have been extended into Friday November 29th, WHILE SUPPLIES LAST. We apologize for any inconvenience.“