Want a Cookie?

https://blog.adobe.com/media_b99c23d82468b10f069414bf2e33c7af36e7b650.gifFirst, a little overview of the purpose of cookies in terms of analytics (not milk!).

Simply put, in the analytics world, cookies are used to track and count unique visitors. Cookies come in two flavors, first party and third party. First party cookies are set by the same domain as the page the user is currently viewing, while third party cookies are set by a domain different from the page the user is currently viewing. As browsers add features to support greater Internet privacy, the acceptance of third party cookies is diminishing.

When cookies are rejected, Adobe uses a fallback method to determine a unique visitor. The fallback method varies depending on the analytics code version implemented on your web site. Broadly speaking, there are three possible fallback methods, the original method using IP address and user agent string, the new fallback method using the s_fid first party cookie, and finally, the option to go with a true first party cookie. This blog post outlines all three methods to help you make the right cookie decision for your analytics needs (with or without milk!).

All code versions previous to H.25.3 use the original fallback method to handle cookie rejection. When a third party or first party cookie is rejected by the browser, Adobe uses a combination of user’s IP address and the user agent string to identify visitors.

Things to keep in mind regarding visitor count:

For analytics code versions from H.25.3 onwards, the code contains a new fallback visitor identification method. If the visitor id cookie is rejected, the code will set a first party cookie using the site’s current domain. The new first party cookie, s_fid, is created and set to a randomly generated unique ID with an expiration of two years. If an s_fid, first party cookie cannot be set, then the Adobe solution will use the original fallback method of IP address and user agent combination.

Things to keep in mind regarding visitor count:

For all versions of the analytics code, first party cookie tracking is the recommended approach. First party cookie implementations provide the most accurate count of visitors because of the very low cookie rejection rate, as well as the guarantee of a unique and persistent visitor id value.

Things to keep in mind regarding visitor count:

Again, it is our recommendation to always use first party cookie tracking when possible. First party cookies will always give you the most accurate visitor count. However, if you need to use third party cookies, the new s_fid fallback method will provide you with a good degree of accuracy. Now that you know how each method works, I hope you can figure out which approach best meets your needs!