Different data GA4 API Connector and Looker Studio

Dear people of ZappySys,

I’ve connected one of our clients’ GA4-data via the ZappySys components. However, it turns out that there are slight differences between the data in Looker Studio (directly connected to the GA4 property) and the data I retrieve by using the API-connector. However, in contrast to Looker Studio, I am combining multiple dimensions at the same time (sessionCampaign, sessionChannelGrouping, sessionMedium and sessionSource). Could that cause the differences between Looker Studio and the results I retrieve from the API-connector? What else could it be?

I’m looking forward to hearing from you,

Kind regards,


Hi @Marijn - Difference can be due to many things. Default Sampling used by Looker Studio, Combination of Dimensions / Metrics.

The only way we can mimic exact same behaviour is checking Fiddler Trace from Both applications (ZappySys vs Looker Studio).

Install and configure fiddler as described below and see request URL / Request body sent by both apps. Findout what is different in both API requests

Contact our support of still have issue.