Google Analytics and DFP discrepancies

If you see significant discrepancies (>10%) between the reports in your DoubleClick for Publishers account and those in Google Analytics, please keep in mind these important points:

  • Analytics tracks page views while DoubleClick for Publishers counts ad impressions. Be sure you are comparing reports that match the appropriate pages in Analytics with the proper slots in the DoubleClick for Publishers reports.
  • Use the inventory reports in DoubleClick for Publishers and segment by ad slots for the most precise comparison.
  • Enable the Unfilled impressions column to see if there are a significant amount of blank ads being served.
  • Verify that DoubleClick for Publishers and Analytics code are both on the same page and in the proper locations within the HTML.
  • Try using the new Analytics asynchronous code for optimal performance.
Even if your code is set up properly, statistics may still differ between DoubleClick for Publishers and Analytics. There are a number of possible explanations.

I. Reasons why an ad impression in DoubleClick for Publishers may not equal a pageview in Google Analytics:

  • Separate JavaScript code: DoubleClick for Publishers counts an ad impression when the DoubleClick for Publishers ad code is executed by a user's browser. Similarly, Analytics counts a pageview only when the Google Analytics tracking code is executed by a user's browser. Because they are located in different parts of your page, it is possible that one of these JavaScript snippets will load and the other will not. For example, because Analytics recommends placing the tracking code at the bottom of your HTML, in very rare cases a user will enter and then exit a page before the page completely loads and before the tracking code is executed. In this case, DoubleClick for Publishers might count an ad impression, but Analytics won't count the pageview. This would result in a higher impression count in DoubleClick for Publishers than pageview count in Analytics. (see above link for new Analytics tags)
  • Iframes: Some publishers have placed DoubleClick for Publishers tags in an iframe to serve ads. Browsers that don't support the <iframe> tag will not report an impression. This can result in Analytics counting more pageviews than DoubleClick for Publishers counts impressions.

For browsers that do support iframe tags, putting the DoubleClick for Publishers tags within an iframe can result in an extra round trip between the browser and server. This additional latency can cause some users to leave the page before the browser has enough time to make the calls to both Analytics and DoubleClick for Publishers.

  • Security (blocking) Software: Your DoubleClick for Publishers impressions might also be decreased by personal firewall software or ad blocking software which can cause Google ads to not display on your site, or may obscure portions of the ad. Ad blocking features of your users' internet security software must be disabled in order to view Google ads.
  • Timezone: If your Analytics timezone doesn't match your DoubleClick for Publishers timezone, then the two sets of reports will be aggregating different time periods for the same displayed date. Learn how to set the time zone for your Google Analytics reports.
  • Analytics profiles: Analytics allows you to create different profiles that can be used to filter data. If you are viewing a profile that filters out some data, then the DoubleClick for Publishers data meant to correspond to the filtered-out data will not be shown. Browse through other articles about creating filters and controlling your report data through them.
II. Things to keep in mind when comparing ad impressions to pageviews:
  • Frames: If the Analytics tracking code is present with a framed page as well as the framing page, Analytics will likely register two pageviews for that visit. This can result in inflated pageviews in Analytics. Learn more about framed sites.
  • _trackPageview function: If you're using the _trackPageview function, your pageviews may be slightly inflated within Google Analytics. _trackPageview works by creating virtual pageviews for specific events such as PDF downloads that won't be tracked in your DoubleClick for Publishers account. Learn more about using virtual pageviews through Special Case Goals and Funnels.