> For the complete documentation index, see [llms.txt](https://docs.hello-lisa.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hello-lisa.com/developers/analytics/google-analytics-4.md).

# Google Analytics 4

The Google Analytics 4 bridge forwards LiSA analytics events (media playback, product interactions, comments, social sharing, stickers) into GA4 as custom `gtag` events, so they appear alongside your other GA4 data.

### Prerequisites

* **GA4 (gtag.js) must already be installed** on the pages that host LiSA (your existing Global Site Tag). The bridge only calls `gtag('event', …)`; it does not load gtag.js.
* A LiSA client id (provided during account setup) — part of the embed `src`.
* Optionally, your GA4 **measurement id** (`G-XXXXXXX`) to route hits to a specific property.

### High-Level Flow

1. **Emission** — LiSA emits a domain event (e.g. a product add-to-cart) on the host page (see Event Delivery).
2. **Bridge** — the bridge calls `gtag('event', '<lsc_event_name>', params)` with the event flattened into flat `lsc_*` parameters.
3. **GA4** — the event is recorded on your property; register the params you care about as custom dimensions/metrics (see Guidelines).
4. **Reporting** — the events and your registered params appear in GA4 reports and Explorations.

### Pages

* [Embed Script](/developers/analytics/google-analytics-4/embed-script.md)
* [Event Delivery](/developers/analytics/google-analytics-4/event-delivery.md)
* [Guidelines](/developers/analytics/google-analytics-4/guidelines.md)
* [Event Reference](/developers/analytics/google-analytics-4/event-reference.md)
* [Sample Events](/developers/analytics/google-analytics-4/sample-events.md)