We Can’t Figure Out Amazon’s Weird Pricing System

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Would you go up or down a dress size if it saved you several hundred dollars? That’s a real possibility at Amazon, where Racked has noticed wild price discrepancies across sizes for the exact same item of clothing.

Like this Halston Heritage evening gown in black.

Sizes 0, 4, 6, 8, 10, 12, and 14 pay $725, which is full-price for this gown. But size 2 gets a big price break: the size 2 gown costs $449.

What gives? Amazon’s dynamic pricing system is often a puzzle, but adding to the mystery is the fact that these items have different prices for different sizes but were all sold and shipped via Amazon — not through different sellers.

A rep for Amazon declined to comment, citing company policy that prohibits Amazon from sharing specifics on pricing.

Here’s more examples of bizarre pricing Amazon differences that seemed to be based solely on size. These are all products that ship from and are sold from Amazon.com, and these are the prices as of today’s publishing.

Gypsy Sport hoodie in black: This could ring in at anywhere from $45 to $132. The large costs more than the medium, the extra large is more than the large, and the small costs $131. This indicates fabric cost isn’t the issue.

Could the pricing have something to do with availability? Both small and extra large only have one sweatshirt left on the site, and those prices are the highest.

Jonathan Simkhai crepe skirt: If you’re a size 4 or size 6, you’ll have to pay full price for this $495 skirt. But size 0 and size 2 cost around $160 and size 10 costs $284.

Again, wondering about the availability issue, but size 6 and size 10 each only have one size in stock and the prices of those two sizes are totally different.

Schutz Women's Mindy sandal in Oyster: If you’re an 7.5, you pay just $40. Size 6.5 will pay $118 for the same shoe. (Prices in other sizes range from $52 to $118).

Betsey Johnson polka dot midi dress: Prices are all over the map for this little polka dot dress. The size 2 costs $38, size 4 costs $44, size 6 costs $59, size 8 costs $38, size 10 costs $38, Size 12 costs $52, and size 14 costs $52. Phew!

Not every item on Amazon Fashion is priced like this, but enough are to make shopping for your size feel like a game of pricing roulette.

Racked emailed a few brands to ask about this pricing weirdness, but the brands indicated that Amazon would have to answer the question — though the possibility of price matching with other retailers was brought up.

For more hypotheses, Racked checked in with retail analytics firm Boomerang Commerce, which was founded by an ex-Amazon employee and is made of up of team members who worked at Amazon, Google, and Walmart.com. Boomerang Commerce provides competitive pricing and assortment technology and data services.

Amazon’s price optimization strategy has allowed the company to win when selling products like electronics and books, Boomerang Commerce’s director of product Albert Chow, PhD, explained via email.

“However, when applied to apparel, the same strategy is resulting in customer confusion. For example, the same color and style dress is listed at different prices and often without a discernible reason,” he said.

Chow brought up this Star Vixen belted lace dress as an example, which ships and is sold by Amazon.com. Every size costs $31.11, except the large, which costs $7.25.

Chow thinks that the most likely reason for this is that Amazon is testing price elasticity and demand of the product by changing the price of one size while keeping the others constant.

Other possible reasons Chow suggests is that the large size is significantly overstocked, or that the demand for the large size is significantly smaller.

But that $24 price difference between the large and the medium could cause shoppers to shake their heads.

“As a customer, instead of clicking on buy, I would be asking myself: If I wait, will my size also be a good deal?” Chow says. “Am I being punished for being an x-large? Is $7.25 is the true value of Star Vixen brand? Why would I pay more than $7.25? Is there something wrong with the large size?”

All valid questions. Could this be a hurdle for Amazon in its ongoing attempts to become a fashion powerhouse? Financial services firm Cowen predicted in July that Amazon will surpass Macy’s to become the top U.S. apparel retailer by 2017. If this trend of unpredictable pricing continues, you might want to befriend your local tailor.