happy tot on amazon
This box of 16 pouches cost 30 cents an ounce, including shipping.

When shopping online last night to find the best deal on baby food, I tried filtering prices from low to high.

But what I got was a confusing mix of results, with a single jar of food being compared with a 16-pack of puree pouches. Of course, a single pouch at $1.47 would be more affordable than 16 pouches at $19.

This is where unit pricing comes into play. Unit pricing allows consumers to quickly compare prices when shopping for toilet paper, breakfast cereal, and in this case, baby food. Knowing how much a product costs per ounce or per cubic yard is critical to finding out if one box or package is cheaper than the other.

For instance, the 16-pack cost 30 cents an ounce while the single pouch of cost 37 cents an ounce. Without the ability to sort by that information, I had to manually sift through thousands of results to find reasonable prices.

To that end, six retailers have agreed to provide new unit pricing online, by the request of New York’s Attorney General Eric Schneiderman. Participating retailers include Walmart, Costco, Walgreens, FreshDirect, CVS and Drugstore.com.

But in a statement issued last week, Schneiderman said Amazon is refusing to participate. Although Amazon displays unit pricing on some of its pages, as was the case in my baby food example, Schneiderman said it does not provide the information uniformly across its platforms. In addition, Amazon’s subsidiaries, including Quidsi, the owner of Diapers.com and Soap.com, do not currently display unit pricing.

The Attorney General said Amazon agreed to extend unit pricing to Quidsi, but refused to commit to that in a written agreement. It also would not agree to extend unit pricing to pages where that information is absent, nor would it commit to continue providing unit pricing information to consumers in the future.

This single pouch would cost $
This pouch costs $2.12 an ounce, including shipping.

An Amazon spokeswoman was still working on a response at the time I published, but I’ll update the story when I hear back.

UPDATE: An Amazon spokeswoman would not elaborate beyond saying, “As you’ll see when you search Amazon.com, unit pricing is included on detail pages.”

Under the agreement, Schneiderman said Walmart and Costco will provide unit pricing information on their websites and mobile stores throughout the U.S. by the end of 2014. Walgreens, FreshDirect, CVS and Drugstore.com will provide unit pricing online by March, 2015. All six chains have agreed to continue providing unit pricing to consumers in the future, including in any online stores they create in the years to come.

However, the information is only useful if the customer can sort by unit pricing, as I found was the case while shopping for baby food. In my experience, Amazon did provide unit pricing on product pages, but did not rank results by that measurement. In addition, in the case of the single pouch, shipping was not included in the unit measurement, so that pouch, which cost $1.47 or 37 cents an ounce, would have cost a whopping $7.42 each, or $2.12 per ounce.

Prior to this initiative, the AG said unit pricing information online was rare among large retailers, with only online grocer Peapod providing the information despite 19 states and the District of Columbia requiring some type of unit pricing.

While listing the unit pricing helps, it will be even more beneficial to the customers to be able to sort by unit pricing, especially as they turn to shopping online for groceries. By 2016, Forrester Research estimates that online grocery sales are projected to reach $21 billion a year in the U.S.

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