DealPicker — how price comparison works | dealpicker.net
A comparison engine compares offers, not products — the same item listed by different sellers under different terms, normalised into one row each.
A comparison shopping website is a vertical search engine that shoppers use to filter and compare products based on price, features, reviews and other criteria. It does not hold stock. It pulls product data from retailer feeds and turns each offer into a row.
The comparison is only as fair as the normalisation. Pack sizes, currencies, tax treatment and delivery windows all have to be converted to a common basis before two rows can be ranked against each other.
On narrow screens, swipe or scroll the plate sideways.
Price is one field. Shipping, tax, stock status, delivery window and return policy are separate fields that change the real cost. A row that shows only the headline number is incomplete.
Coverage is the other half of the picture. Most comparison shopping sites aggregate product listings from many different retailers but do not directly sell products themselves, so a retailer absent from the feed is absent from the comparison.
The practical test is unit price plus landed cost. If a row gives you both, it is comparable. If it gives you neither, it is a headline, not a comparison.
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