What is Google Auto Tagging?

[TTFV]

Google Ads can (and does by default) attach a code called a GCLID to the end of the URL. This can be interpreted by Google Analytics and also integrated back into conversion tracking in Google Ads using offline conversions or the API.

It’s generally set it and forget it compared to manual tracking systems such as value track and UTM tracking codes.

[fathom53]

Google has a whole [support doc page](https://support.google.com/google-ads/answer/3095550?hl=en) on this.