Conversion tracking in AdWords is the method for counting the number of people who reach a site through a paid search ad that perform an action of interest. That action can be anything from signing up for a newsletter to requesting more service information to making a purchase. A site owner defines these conversions by placing a snippet of AdWords-generated code on the thank-you page that comes immediately after a conversion is complete (so for a purchase, the code would appear on the receipt page). Within AdWords, you can even label the conversion action for easier reference and then generate unique conversion codes for each type.
However, there has always been the issue of not being able to precisely count how many conversion actions registered in AdWords came from one single visitor. For example, if you report individual leads to your CRM system, you might be more interested in the number of people who engaged in at least one desired action rather than merely the total number of different actions completed.
Now Google has taken a step toward clearing up this issue. The Inside AdWords blog reports the new change in conversion reporting that now differentiates between conversion actions/transactions (called “many-per-click conversions”) and converting visitors (called “1-per-click conversions”). The cost per conversion metric are also calculated separately.
The new metrics will soon be rolled out to AdWords Editor and the AdWords API, but they’re not quite there yet.
*NOTE* A single visitor may theoretically be counted twice if that visitor clicks through another ad after a 30-day period from their first click. (This is because the cookie Google uses for conversion tracking expires after 30 days).