How to use the GA4 Custom Dimension Builder

Type the business concept (e.g., Subscription Plan). Pick scope: Event (varies per event), User (set once per user), or Item (e-commerce). Type an example value. The tool generates GA4 Admin values, dataLayer push code, and GTM variable setup.

Pourquoi cet outil est important

Custom dimensions are how you turn GA4 into a business-specific data warehouse. Without them you cannot answer questions like what conversion rate do users on the Pro plan have or which content author drives most signups. Setting them up correctly first time saves weeks of cleanup later.

Cas d'utilisation courants

• Building dimension catalogs for new GA4 properties
• Standardizing tracking specs across teams
• Helping developers implement first-pass
• Documenting dimension specifications
• Migrating UA custom dimensions to GA4

Event vs User vs Item scope

Event scope: the value can change per event. User scope: set once and persists for the user. Item scope: for e-commerce item-level dimensions. Pick wrong and your reports show wrong patterns.

Foire aux questions

Do I need to register every parameter?
No. Parameters pass with events automatically. Registering a custom dimension lets you use it in standard reports and segments.

Why is there a 24-48 hour delay?
GA4 batches dimension registration. Standard reports take 24-48 hours. Explorations use them immediately.

What is the limit?
50 event-scoped, 25 user-scoped, 10 item-scoped per property (free GA4).

Can I rename after registering?
Yes, the display name. The parameter name (in code) is immutable.