Measurement is about whether GA4 is counting the right things at the right granularity. Clean data that counts the wrong conversions, or uses inconsistent event names, produces reports that look healthy but answer the wrong questions.
Chapter 4 of 6 · GA4
Layer 3: Measurement Audit
Audit whether GA4 is counting the right conversions with consistent event naming and correctly scoped custom dimensions. Chapter 4 of the GA4 Best Practice guide.
2 min read
Four events that represent real business value are marked; high-volume behavioural events stay unmarked. If everything is a key event, nothing is.
| Check | What to look for | Pass condition | Fix if failing |
|---|---|---|---|
| Key event count | How many events are marked as key events? | 3-5 events representing real business outcomes (purchase, lead, booking, call) | Unmark vanity events (scroll, page_view, video_start); mark the ones that matter |
| Conversion counting | Is counting set to "once per event" or "once per session" for each key event? | Lead forms: once per session. Purchases: once per event. | Change in Admin: Events — click a key event and adjust counting method |
| Event naming consistency | Are all events in snake_case? Any duplicates (button_click and buttonClick)? | All events lowercase snake_case; no duplicate event names for the same action | Standardise in GTM; GA4 treats event names as case-sensitive |
| Recommended events used | Is purchase used for transactions? generate_lead for lead forms? |
Google recommended events used wherever applicable | Rename custom events to match recommended schema — unlocks GA4 ecommerce and bidding features |
| Custom dimensions registered | Are all important custom parameters registered as custom dimensions? | Every parameter you want to filter or report on is registered in Admin: Custom Definitions | Register missing dimensions; note that registration is not retroactive for user-scoped dimensions |
| Event volume sanity | How many unique event names exist in the account? | Under 50 for most sites; more than 100 is a warning sign of sprawl | Audit and consolidate; use parameters to differentiate instead of new event names |
Before
Three spellings split one action — every report undercounts.
After
One snake_case name; the full 737 shows in every report.
GA4 event names are case-sensitive, so formSubmit and form_submit are different events forever. Standardise before the history splits.
Advertisement
i