Why Your Conversions Don't Match (And How to Fix Attribution)

"GA4 shows 120 conversions, Google Ads shows 180, and our CRM shows 95." If that sounds familiar, you're not broken — you're seeing three different attribution models measuring three different things.

They count different events

Ad platforms count ad-attributed conversions, often with view-through. GA4 counts key events on your site. Your CRM counts qualified outcomes. Apples, oranges, pears.

They use different attribution windows

A 30-day click window vs a 90-day window will never reconcile. Align windows before comparing anything.

They de-duplicate differently

Cross-device and modeled conversions inflate platform numbers relative to GA4's session-based counting.

What to actually do

1. Pick one source of truth for each decision (usually GA4 for site behavior, the CRM for revenue).
2. Stop expecting platforms to match — measure trend and direction, not absolute parity.
3. Pipe GA4 into BigQuery so you can model attribution on raw events instead of arguing about dashboards.

Accurate doesn't mean identical. It means defensible.