Conversion Linker is a special tag in Google Tag Manager (GTM) that saves ad click data (like GCLID) in first-party cookies on your domain. This helps link conversions to ad clicks accurately, even when third-party cookies are no longer available.
Now, Conversion Linker has been upgraded to support dual storage: it saves ad click data not just in cookies but also in the browser’s local storage.
Why is this update important?
1. Resilience against tracking restrictions: local storage is less affected by browser-imposed cookie limitations. This makes tracking more reliable, even in stricter environments like Safari’s ITP.
2. Extended data retention: data in local storage persists longer than cookies, especially when users close their browsers. This ensures more accurate tracking of delayed conversions.
3. Flexibility: dual storage significantly increases the chances of successful attribution, even in challenging browser conditions.
Previously, Conversion Linker was the go-to tool for saving ad click data using first-party cookies. With this update, it’s become even more reliable — crucial now that GoogleAds can no longer depend on third-party tracking for conversions.
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