Retailers, using new, fast computer algorithms, are changing their online prices of products from laundry detergent to toaster ovens on an hour-by-hour and sometimes minute-by-minute basis, The Wall Street Journal reported Wednesday.
"In the age of the Internet, fixed prices are a thing of the past," said Oren Etzioni, professor of computer science at the University of Washington and co-founder of Decide.com.
In one example, the price of a General Electric microwave oven from sellers on Amazon.com changed nine times in one day, with the price fluctuating between $744.46 and $871.49, the Journal reported.
Best Buy responded by lifting its online price on the oven to $899.99 from $809.99 after the Amazon prices rose, then lowered it again after Amazon prices dropped.
The most frequent price adjustments are made by Web stores selling products on Amazon and hoping to maintain the lowest price, even if just by a little and just briefly, so their products will show up at the top of the search results by shoppers doing price comparisons.
The most frequent changes are for consumer electronics, clothing, shoes, jewelry and household staples like detergent and razor blades, the Journal reported.