Have you ever been browsing around Yahoo! Shopping or Shopping.com clicking on various products. You see a product you like, read about it, click around to some of the merchants that sell it, click on another product, read about it, …. Well, whether you realize it or not, each one of those clicks from the shopping comparison site to the merchant’s web site costs money for that merchant. Brian Smith over at ComparisonEngines.com put together a nice table listing the minimum rates each of four popular shopping comparison sites charge merchants for various product categories.

CPC Price Floors on the Shopping Comparison Engines

A few months back when I was shopping for a plasma TV, I spent a long time browsing through various models on Yahoo! Shopping and clicking through to various merchants. There’s a good chance I earned Yahoo! Shopping well over $20. Unfortunately for Y!’s merchant advertisers, I ended up buying the TV through an alternate source. Sorry Y! merchants!!

What surprised me was ink and toner cartridges also tops the list with a minimum of $1/click. I wonder if the high CPC is because of a high gross profit margin in this category (how much profit does a merchant make on a $30 ink cartridge… $1, $5, $10??) and/or high conversion rates amongst users in this category (x?/100 users who click actually follow through with a purchase?) I’ve got a contact who manages SEM at an online office tech retailer so hopefully I can get an answer for this question in a few days.