gclid?The unique token Google Ads appends to every ad click so the advertiser's site can report your visit and purchases back to Google.
This page covers the whole Google Ads family: gclid, gclsrc (which Google product issued the click), dclid (the Display and Campaign Manager equivalent), and the newer gad_source and gad_campaignid markers.
When you click a Google ad with auto-tagging on (it is on by default for virtually every advertiser), Google appends gclid, a one-time token identifying that exact click: the ad, the keyword, the auction, the moment.
The advertiser's site stores it in first-party cookies (_gcl_aw and friends) via the Google tag. When you later buy something or fill a form, the site fires a conversion event carrying the token back to Google, which links it to your click and, through your Google account, to you. It powers the advertiser's conversion reports, Google's bidding algorithms, and remarketing lists.
dclid does the same job for Display and Video campaigns booked through Campaign Manager, gclsrc records which Google product issued the identifier, and gad_source appeared in 2023 as an extra marker on ad traffic.
Yes. These tokens exist purely for attribution; no legitimate page changes its content based on them. In the rare case a landing page validates the presence of gclid for its own bookkeeping, it still renders. Removing the token simply means the advertiser's dashboard records one less tracked conversion.
Rather's Link Shortener strips gclid and hundreds of parameters like it, right in the address bar and in everything you copy or share. Free, open source, no account, no data collection, and the page you are on never breaks: the cleanup happens after the site has already loaded.