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The retailers topped Internet Explorer and Firefox consistency tests, respectively.
Apple.com had the best consistency score in Internet Explorer testing among large retailers measured in December, says Compuware Gomez. Last month, the retailer had the most consistent Internet Explorer site loading time with a variation of 0.64 seconds. Overstock.com had the best Firefox consistency score at 0.73 seconds.
Dell.com (0.73 seconds) placed second in Internet Explorer tests. Overstock.com (0.76) came in third, followed by Costco.com (0.84) and OfficeMax.com (0.99) in fifth.
In Firefox testing, LLBean.com came in second place behind Overstock.com with a variation of 0.74 seconds. Apple.com was next (0.75), followed by OfficeMax.com (1.03) and Costco.com (1.09).
The average Internet Explorer consistency score among the 21 retailers measured in December was 1.95 seconds. The same group of retailers produced an average Firefox score of 2.12 seconds.
The consistency ratings take into account differences in the speed of web page delivery across multiple visits.
Click here for the full test results.