If Meta is showing 5x more purchase value than Google Analytics, the discrepancy is likely due to differences in attribution models, tracking methods, or blocked data. Here’s a breakdown of what could be causing it:
1) Attribution Window Differences
Meta uses a default 7-day click / 1-day view attribution model.
Google Analytics (GA4) often uses last-click attribution unless customized.
→ Result: Meta claims credit for more conversions, even if they didn’t happen immediately.
2) Cross-Device or Cross-Browser Tracking Gaps
Meta can track users across devices (via login), while GA loses visibility when a user clicks on an ad on mobile but purchases later on desktop.
3) Ad Blockers and iOS Privacy (GA Impacted More)
GA tracking is easier to block (cookies or JavaScript), especially on Safari/iOS.
Meta’s tracking via Conversions API (CAPI) is more resilient.
4) Improper UTM Tracking or Landing Page Redirects
If your UTM tags are misconfigured or stripped during redirects, GA may fail to attribute traffic properly.
5) CAPI Overcounting or Duplicate Event IDs in Meta
If Meta’s pixel and server events are not deduplicated properly, you may see inflated results.
What to Check and Fix:
- Compare attribution models between Meta and GA (last-click vs. view-through).
- Ensure UTM parameters are correctly applied and consistent.
- Review pixel + CAPI setup to avoid double-counting in Meta.
- Use Meta's Attribution Settings to match GA settings for better comparison.
- Cross-reference GA conversions with server-side logs (if possible) for accuracy.