A click ID is a unique identifier an ad platform generates for one ad click and appends to your landing page URL: gclid for Google Ads, fbclid for Meta, msclkid for Microsoft Advertising, ttclid for TikTok and many more.
Why It Matters
It’s the only link between a visit and the click that paid for it. Ad platforms use click IDs to match offline conversions, and you can use them to audit paid traffic and attribution. Click IDs are generally treated as personal data under GDPR, so collect them under your own legal basis.
In d8a.tech
The most common click IDs have dedicated event and session columns, paid click IDs drive source and medium, and the full landing URL keeps every other click ID queryable.