The three layers of tracking
URL parameters (utm_*, fbclid, gclid) tell the landing page where the visit came from. They survive the click.
Redirects let intermediaries (ad networks, shorteners, email platforms) log the click before forwarding the user. The user sees a small delay; the platform gets a row in its database.
Pixels and scripts on the destination page tie the visit to a session, a cookie, and any later conversion event.
Click identifiers
Google Ads adds gclid, Microsoft Ads adds msclkid, Facebook adds fbclid. These opaque identifiers let the ad platform match a click on the ad to a conversion logged by its pixel.
Click IDs are personal enough that they often get stripped for privacy. The Bulk URL Cleaner removes them in one pass.
First-touch vs last-touch attribution
Last-touch attribution credits the final click before a conversion. It's simple but ignores the journey.
First-touch credits the very first click that introduced the user. Multi-touch models split credit across all the steps. UTMs and click IDs feed all three.
Respecting users and the law
Tracking parameters are visible in the URL. Don't pass anything personally identifying through them.
Privacy regulations like GDPR require user consent before dropping tracking cookies. Make sure your tags fire only after consent is granted.