Full Answer
Attribution window = post-click counting period. FB: 7-day, GA4: 90-day. Causes number mismatch.
Cherry Seed
What is an attribution window?
data discrepancy
conversion mismatch
cross-platform reporting
Quick Answer
Time period after ad interaction where platform counts conversions. Facebook default: 7-day click, 1-day view. GA4 default: 90 days. Same user journey = different attribution results depending on conversion timing and window settings.