Problem summary
Your Google Analytics 4 (GA4) session total in Funnel can differ from the total shown in GA4 even when individual rows match.
Error message or symptoms
The sum of session values in Funnel differs from the GA4 Totals row.
Sessions or Engaged sessions values are too high when you include dimensions such as Event name, Page path, Page title or Date.
Individual rows match, but the totals differ.
When does this occur
You compare the sum of the session values in each row with the estimated GA4 total.
Your data source includes dimensions that associate one session with multiple events, pages or dates.
A session crosses midnight and appears on more than one date.
Root cause
GA4 uses an event-based data model. One session can contain many events and page views. Dimensions such as Event name can cause the same session to appear in multiple rows. If you add these rows together, you can count the session more than once.
GA4 estimates the unique session total. Funnel adds the values for the selected dimensions. Therefore, the Funnel total might not match the estimated GA4 total.
The same row-level behavior has affected Engaged sessions since September 12, 2023.
For example, GA4 can estimate 349,837 sessions. The values for Sessions on the session_start event can total 348,921. The values for Event count can total 353,573.
Solution
Review the dimensions in your GA4 data source and remove dimensions that are not required for session reporting.
Use Sessions (event based) to count
session_startevents, or use Sessions (session based) to count sessions associated with thesession_startevent.
Compare values that use the same dimensions. Do not compare the sum of detailed rows with GA4's estimated total.
If you need Page path or Page title, create one data source for detailed reporting and another for session totals.
Include Page path or Page title only in the detailed data source.
Filter downstream reports by data source to prevent double counting.
Sessions (event based) and Sessions (session based) can produce values close to the GA4 estimate. The values might not match the estimate exactly.
Sessions (event based):
Sessions (session based):
Funnel does not provide a standard metric that corrects Engaged sessions totals. If you need this calculation, create a custom engaged-session metric that uses the same event-based method as the Funnel session metrics.