# We defined all our audiences in GA4, how do those map to Croct audiences?

Asked by josh_t on 2026-01-15. Tags: ga4, audiences, migration.

We are a B2B SaaS and over the past three years we have built up a
fairly large library of GA4 audience definitions (returning visitors, pricing
page viewers, multi-session evaluators, and so on). We are rolling out Croct for
on-site personalization this quarter.

My checklist questions:

1. Is there any way to import GA4 audience definitions, or do we rebuild them?
2. If we rebuild, how hard is the translation for typical behavioral
   definitions?
3. What is the practical difference between an audience in an analytics tool
   and one used for on-site personalization? I want to set expectations
   correctly with the team.

## 2 answers

### Accepted answer from Croct Bot (2026-01-16)

There is no importer, and the rebuild is the smaller part of the work. The
bigger shift is architectural, which answers your third question.

A GA4 audience is a batch-computed list: users accumulate into it after
processing. A Croct audience is a CQL condition evaluated in real time on
every interaction, as explained in the [audience overview](https://docs.croct.com/explanation/audience/introduction). Nobody is "in" an audience ahead of time; the condition
either holds for this visitor right now or it does not. The practical
consequence is that the audience applies on the same visit where the behavior
happens, rather than after a processing delay.

On translation: most GA4 behavioral definitions map to short CQL expressions.
A few examples:

```cql
user is returning
user has viewed a page with path "/pricing"
session's stats' pageviews > 3
campaign's source is "google"
```

You have [100+ signals](https://docs.croct.com/reference/cql/data-types) to work with across Events, Location, Marketing,
Session, Shopping, User, Web, and Technology, plus custom attributes, so the
typical definition takes a minute or two to rebuild. The post on
[how Croct differs from analytics platforms](https://blog.croct.com/post/croct-vs-analytics-platforms)
covers the analytics-audience versus real-time-audience distinction in more
depth.

### Answer from danilo76 (2026-01-17)

We did this exact migration last year. One tip: do not rebuild everything.
Years of GA4 audiences usually include a long tail nobody uses. We listed the
audiences actually referenced in reports or campaigns and rebuilt those, which
turned out to be about a quarter of the library. Also worth knowing that the
audience estimator in Croct shows you the size of a condition as you write it,
which made it easy to check that our translations captured a similar
population to the GA4 originals.