Markitech / GA4 AI Agent / GA4 Custom Dimensions
GA4 custom dimensions, chosen on purpose
Register the parameters you will actually report on, at the right scope, within GA4 limits.
Updated November 4, 2026 · Markitech team
A parameter sent to GA4 is not reportable until it is registered as a custom dimension or metric. Properties have limits, and the scope you pick (event, user or item) changes what the data means.
Markitech compares what you send with what is registered, flags gaps and waste, and proposes a list that fits your reporting needs.
How to do it
- List parameters currently sent per event.
- Decide which ones need reporting.
- Pick scope: event, user or item.
- Check against property limits.
- Register and name consistently.
- Validate in reports after 24 to 48 hours.
Common mistakes
- Registering high-cardinality values like IDs as dimensions.
- Using user scope for values that change per event.
- Hitting limits with unused dimensions.
- Inconsistent names between GTM and GA4.
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Approved by you, every time
Markitech proposes each change in chat and holds it until you approve. Nothing is published, created or changed in your accounts without that approval.
Part of the GA4 AI Agent guide.
GA4 Custom Dimensions questions
Are there limits?
Yes. Standard GA4 properties have caps on custom dimensions and metrics, so prioritizing matters.
Does it backfill data?
No. GA4 dimensions only apply from the time they are registered.