# Amazon Unit Price Anomalies

Backstory: we get Kirkland almond butter from Amazon, because it has consistently good quality at a reasonable price. Kirkland being the Costco house brand, we’re obviously buying it from someone arbitraging the Costco price. The nearest Costco is over an hour away, so spending \$60 for a membership (*) just to get almond butter doesn’t make sense.

However, I’ve discovered Amazon’s “buy it again” prompting generally doesn’t offer the best deal, so I start each purchase cycle with a general search. The current results proved interesting (clicky for more dots):

Let’s go through this slowly.

The first result shows the “unit pricing” isn’t done automatically, because it’s completely wrong:

I can figure half of \$27.52 isn’t \$9.17, but dividing \$27.52 by three really is. Dividing by two, the actual size, says the correct “unit price” is \$13.76 each. Oddly, searching a day later showed the price went up to \$28.69, with the same incorrect divide-by-three unit pricing error.

The “Amazon’s Choice” result simply means a bunch of people bought from that listing, not that Amazon has an actual involvement apart from raking in their take. There’s no unit pricing, but each jar works out to \$13.59.

The last result confirms Amazon’s unit pricing bogosity by (correctly!) dividing \$26.23 by two, but then claiming the unit price is “per ounce”.

Weirdly, everybody selling the two-pack prices it that way:

We’re surely not looking at half a dozen heads of the same hydra, so this bogosity derives from the commingled UPC (ASIN, whatever) warehouse stock technique giving Amazon a way to avoid responsibility for counterfeits. Somebody (presumably at Amazon) selected the calculation to produce the unit price, but fat-fingered “per ounce” rather than “per each”, and now vendors just bid for that UPC without sweating the details.

You’d (well, I’d) think a bit of Amazon’s much-vaunted machine learning would go a long way toward sorting this out, but it doesn’t.

Word: any sufficiently advanced stupidity is indistinguishable from malice.

(*) Right now, it’s \$8.79 direct from Costco online and their 5% non-member surcharge seems survivable.

## 4 thoughts on “Amazon Unit Price Anomalies”

1. Keith Ward says:

We are all just pawns in the game of the large corporations. At least we can price compare like never before pretty quickly. It just goes to show that you can’t trust an single source to give you a good deal much less the best deal. Everyone needs to keep in mind that they are not our to make your life better but simply make more money for their stockholders. It might be an ugly realization for some but honestly, I’m not sure how one couldn’t know this.

1. Ed says:

Amazon used to have pretty good prices on most things, but it’s become impossible to find “Amazon” amid all the “Marketplace” sellers.

I’m moving back to buying from ordinary retail outlets (well, their online stores), because I’m no longer sure what I’m going to get from Amazon, nor whether it’s a reasonable deal.

Which means I probably won’t renew my Prime membership, because paying a couple of bucks a week for “free” two-day delivery just isn’t as compelling as it used to be and all the other junk mashed into Prime is of no interest.

2. david says: