What Is This?

Digital marketing tool such as email service providers and analytics platforms often append tracking parameters to URLs. These are helpful for marketers, but can also severely decrease the effectiveness of page caching tools such as Varnish.

The purpose of this repository is to keep a centralized list of tracking query parameters used by the huge range of online marketing tools in use today.

The List

Name Platform Confirmed In Unique Per Visitor
fbclid Facebook
gclid Google AdWords / Google Analytics
gclsrc Google DoubleClick
utm_content Google Analytics
utm_term Google Analytics
utm_campaign Google Analytics
utm_medium Google Analytics
utm_source Google Analytics
_ga Google Analytics
mc_cid Mailchimp
mc_eid Mailchimp
_bta_tid Bronto
_bta_c Bronto
trk_contact Listrak
trk_msg Listrak
trk_module Listrak
trk_sid Listrak
gdfms GoDataFeed
gdftrk GoDataFeed
gdffi GoDataFeed
_ke Klaviyo
redirect_log_mongo_id Springbot
redirect_mongo_id Springbot
sb_referer_host Springbot
mkwid Marin
pcrid Marin
ef_id Adobe Advertising Cloud Yes
s_kwcid Adobe Analytics
msclkid Microsoft Advertising Yes
dm_i dotdigital Yes
epik Pinterest Yes

The lists is contained in params.csv. The file contains 4 columns…

The intention is to use this list to form a blacklist for your page cache implementation.


If you come across a tracking parameter that is missing from this list, by all means, make a contribution. In order to do so, please fork the repository and issue a pull request to the master branch. Please include the “Confirmed In” column to show where this query parameter is referenced.