What goes to GA4
When a visitor enters a test, GA4 gets an experience_impression event through the gtag or Tag Manager already on your site, so you can build audiences and reports on it.
What comes back from GA4
Connect your GA4 property in Integrations, and Insights ranks your pages by what a +20% lift is worth and how long a test would take, from your full history. EarlyCRO only reads, and only landing page totals. It uses GA4 to choose what to test, never to judge a test: a result comes from your real orders and goals.
Google Tag Manager
Keep the EarlyCRO script in your page's head rather than in a Tag Manager tag. Tag Manager loads too late to change a page before it paints.
EarlyCRO reads the standard GA4 events in your dataLayer, like add_to_cart, begin_checkout and purchase, so they work as goals with nothing extra to tag. One order counts once, even if it arrives through both gtag and Tag Manager. On Shopify the EarlyCRO pixel covers this instead.
Click data
The script records clicks, scroll depth and pages visited. That means three things you can't do from GA4 alone:
- See how each version of a test changed what people did, not just whether they converted.
- Turn any clicked element into a goal after the fact, with its history included.
- See the common paths through your site, and where people leave.
All of this explains a result. It doesn't decide one. With dozens of things to compare, something always looks different by chance, which is why only the goal you chose up front can call a winner.
Consent
EarlyCRO follows Google Consent Mode. While analytics is denied, nothing is sent, and whatever was held back goes once it's allowed. If your banner doesn't use Consent Mode, call CRO.setConsent(true) or CRO.setConsent(false) from it. Assigning a version happens in the browser and sends nothing.