Meta counts ad views within its own window; GA4 only counts the last click. A 20-40% gap is normal — neither number is wrong. To know Meta is genuinely driving growth, test it directly by increasing spend and watching topline revenue move with it.
- Meta credits view-through conversions. GA4 doesn't. That's most of the gap.
- 20-40% Meta-vs-GA4 gap is normal. Beyond ~50%, suspect a tracking fault.
- The strongest proof Meta is working: increase spend and watch topline revenue rise with it, not just the platform's own numbers.
Why they disagree
Meta asks "did someone who saw or clicked my ad convert within my window?" GA4 asks "what was the last non-direct click before this conversion?" Different questions, different numbers — neither is broken.
What's normal
Meta reporting 20-40% more conversions than GA4 is typical for e-commerce. Beyond ~50%, look for duplicate events or broken tags before blaming attribution.
The strongest proof: watch the topline
Reconciling the two numbers makes your reporting consistent. But the real confidence comes from a simpler test: increase Meta spend 30-50% for one to two weeks and watch total business revenue — not just the platform dashboard.
When topline moves up with it, that's the clearest signal you have: Meta isn't just reporting conversions, it's genuinely growing the business. That's the basis for scaling with confidence, not a guess.
This is the test we run before recommending a client scale a channel further. It turns "the dashboard looks good" into "the business is genuinely growing" — and that's the difference that lets you invest with confidence.
Related service: Analytics & Attribution