There’s a lot of confusion regarding Google’s recent change to conversion metrics with the AdWords conversion tracker.  Previously a “1” in the “Conversion” column would tell you there was at least one conversion that happened within 30 days of that date. You were happy with this limited knowledge.

Messy and/or complex data was disguised as clean & simple data.  The “1” was all you knew.  If the user clicked an ad and purchased something, you’d see a “1.”  If the user bookmarked the page with the conversion tracking script and went back to it a week later, you’d still see a “1.”  If another purchase was made two weeks later, you’d still see a “1.”  Simple, right?

In early April, Google exposed some of the potential mess to be more in line with the way conversions and transactions are tabulated in DoubleClick and other online ad platforms.  They changed the name of “Conversions” to “Conversions (1-per-click)” and added a new metric called “Conversions (many-per-click)”.  While the 1-per-click conversion spot can only be filled once, the many-per-click conversions are incremented whenever any of your conversion scripts run within 30 days after a click.

Under the new system, consider the following scenarios and what conversions would be tracked for each:


The user clicks an ad, goes to the landing page, then opts-in to an email newsletter.  This triggers a lead conversion.

Conversions (one per click): 1
Conversions (many per click): 1

The user refreshes the conversion page:

Conversions (one per click): 1
Conversions (many per click): 2

The user returns to the lead conversion page a week later from a bookmarked link:

Conversions (one per click): 1
Conversions (many per click): 3

The user gets an email from your company two weeks later and then buys something, triggering a sale conversion:

Conversions (one per click): 1
Conversions (many per click): 4

The above scenarios highlight the increased importance of clean data.  The new many-per-click conversion tracking stats may be telling you nothing more than the fact that you’ve got a messy conversion tracking installation.

The problem can be magnified with additional metrics available in AdWords Reports.  Reports give you the option to display columns revealing the exact number of each “type” of conversion… whether “lead,” “sale,” “sign-up,” “page view,” or “other.”  These values, however, are all of the many-per-click variety.

Let’s revisit the scenario above, this time with some additional metrics available in the reports:

The user clicks an ad, goes to the landing page, then opts-in to an email newsletter.  This triggers a lead conversion.

Conversions (one per click): 1
Conversions (many per click): 1
Lead Conv. (many-per-click): 1

The user refreshes the conversion page:

Conversions (one per click): 1
Conversions (many per click): 2 (incremented by 1)
Lead Conv. (many-per-click): 2 (incremented by 1)

The user returns to the lead conversion page a week later from a bookmarked link:

Conversions (one per click): 1
Conversions (many per click): 3 (incremented by 1)
Lead Conv. (many-per-click): 3 (incremented by 1)

The user gets an email from your company two weeks later and then buys something, triggering a sale conversion with a value set at “$100”:

Conversions (one per click): 1
Conversions (many per click): 4 (incremented by 1)
Lead Conv. (many-per-click): 3
Sales Conv. (many-per-click): 1 (incremented by 1)
Sales Conv. Value (many-per-click): $100

The user clicks through to a few pages on the site, then uses the back button in their browser to return to the page with the sale conversion tracking code:

Conversions (one per click): 1
Conversions (many per click): 5 (incremented by 1)
Lead Conv. (many-per-click): 3
Sales Conv. (many-per-click): 2 (incremented by 1)
Sales Conv. Value (many-per-click): $200 (incremented by $100)

Reliable tracking is imperative, especially when tracking non-sale and sale conversions together.  In the last example above, the “2” sale conversions were really only a single conversion.  There is no way to tease the true number out of the data.

Track it once. Clean up your conversion funnel tracking to ensure the tracking script runs only once per conversion. You’ll need your web developer’s help with this, but there are two primary methods to make sure a single conversion is only counted once:

Better Tracking: Put the conversion tracking script on a page that automatically redirects to the “real” thank-you page after a second or two. This will keep the conversion tracking page from being bookmarked, but won’t restrict the “back” button from triggering another conversion on the conversion page reload.

Best Tracking: Set a cookie on the thank-you page with the conversion tracking script. This cookie value can be set to “first-view” for the first view of the page.  If the page is reloaded, set the cookie value to “repeat-view.”  The trick is to test for this cookie value before running the conversion tracking script.  Only run the script if this is the “first-view.”  The cookie should be valid for at least 30 days duration.

Once your data is clean, you can start making sense of the conversion stats.  You’ll have reason to be confident in your bid decisions and ROI.

Editor’s Note: Proper conversion tracking is only one piece of the puzzle when it comes to making your count efficient and avoiding wasted spend. This special report details more ways you can diagnose (and cut!) wasted spend in your account.