Google analytics vs Adwords conversions

Question

I wonder if you can help.

We have an ecommerce site. We integrate with both PayPal and WorldPay for our payments, and have added both secure.worldpay.com and paypal.com into the list of referral exclusions in Analytics. We have also added Adwords conversion tracking to the receipt page of our checkout process.

The problem we are experiencing is that the conversions being shown in adwords, is not the same as what Analytics is telling us. If I take this Monday for example. We had 14 orders. Adwords tells us it converted 13 of those orders, yet Analytics attributes 7 to CPC and 7 to organic.

We find ourselves in this really awkward position where we dont know which Google product to trust! Do we spend more on adwords believing that it converts almost all of our orders, or do we spend less considering it only accounts for 50% of the conversions!

We have one final weird issue, whereby every so often the ecommerce data will not be sent to Analytics. Is there anyway of getting ecommerce tracking data back from the call to check if there was an error?

Many thanks in advance dotdev

Answer 1

Google Adwords and Google Analytics measure conversions in different ways.

Google Adwords tracks clicks on ads, and when coupled to Google Analytics attributes conversions in a 30-day window to the ad (default setting). Read as: if someone makes a purchase within 30 days after clicking on an ad, it's because they have seen the ad.

Google Analytics mostly attributes conversions using last-click attribution, which means that the medium/source of the last click is given to the conversion.

If a user clicks on an ad for great headphones and ends up on a product detail page of headphones on website X. Then decides to leave website X to compare the headphones with offerings of other vendors: website Y and Z. Finally the user decides to return to the first website X by typing in "headphones website x" in a popular search engine (not clicking any ads).

Google Adwords will contribute the conversion to it's doing ("See that user clicked my ad and bought headphones within 30 days"). However Google Analytics will attribute that conversion to the organic channel ("That user that bought those headphones, the last time I saw him he came from a search engine, that's organic").

Another difference between Google Adwords and Google Analytics is that Adwords dates it's conversion on the time of the click on the ad, Google Analytics dates it's conversion on the date it takes place. So if the ad is clicked on Wednesday and the conversion takes place on friday, Adwords will date the conversion on wednesday and Google Analytics will date the conversion on Thursday.

See this article: Why do conversions reported by AdWords, Google Analytics, Digital Analytics, and Floodlight not match? https://support.google.com/ds/answer/2791195?hl=en