Different values from other web analytics solutions
Different web analytics products may use a variety of methods to track visits to your website. Therefore, it is normal to see discrepancies between reports created by various products. However, we generally believe that the best way to think of metrics across different web analytics programs is to think in terms of trends, as opposed to numbers by themselves.
One example is to compare related metrics, such as pageviews (e.g., 15% of traffic went to page x). In addition, the comparison of data over time could be valuable--information such as "conversions increased by 20% over the past 3 months," or "our site gained 10% more pageviews in the month of March." In most cases, you'll notice that different analytics solutions, though different in numbers, will generally depict the same trends.
While we're not able to provide side-by-side comparisons of Google Analytics with other web tracking solutions, the following list points out some of the main reasons your actual numbers may differ:
- Terminology: The terminology used in one program may not mean the same thing or may not be measured the same way as in another program. Pageviews are generally similar between vendors; however, it's much more difficult to define a visit or a visitor. In Analytics, if a user comes to your site twice within thirty minutes without closing the browser, that registers as one visit. Other web analytics solutions may treat this behavior as two visits, depending on their definitions.
- Tracking methods: There are two main methods of tracking activity: cookie-based and IP + User Agent.
- Cookie-based tracking relies on parcel of text sent back and forth between a web browser and the server it accesses, commonly called a cookie. Every web analytics solution can have different default and customizable options for cookies. Learn more about Google Analytics cookies usage on websites.
- IP + User Agent tracking typically uses log-file analysis for its data. This may report higher numbers than reported by cookie-based tracking because of dynamically assigned IP addresses and spider and robot visits.
- 1st party vs. 3rd party cookies: Even among cookie-based tracking solutions, there's a difference between 1st-party and 3rd-party cookies. Because 3rd-party cookies are set by a source other than the website being visited, they're often blocked by browsers and security software.
- 3rd-party images: Some browsers give users the option to disable images that are requested from domains other than the current page.
- Filters/settings: Many web analytics solutions provide data filters. Differences in the way that filters are applied, or creating different filtering altogether, can drastically affect the data in your reports.
- Timezone differences: If your web analytics solutions group data using different timezones, your daily or hourly data is affected.
- Visitor browser preferences: Any technology that a user uninstalls, blocks, or otherwise disables cannot be used as an analytics tracking method.
- Caching: Depending on the analytics solution, a visit to a page that has been cached may or may not be counted as a page visit.
- Attribution differences: Google Analytics uses a “near last click” attribution model as default. Other sources might use a true last click, or otherwise to attribute goal or revenue data.