Automatically collected events
Automatically collected events are events GA4 logs by default once the tag or SDK is present, without you instrumenting them — first_visit, session_start, user_engagement, and app lifecycle events among them. They are distinct from enhanced measurement (auto web-interaction events you toggle) and from recommended/custom events you send yourself. Knowing what is automatic prevents you from re-instrumenting events GA4 already provides.
What counts as automatic
Once GA4 is installed, certain events are logged without configuration: web events like first_visit, session_start, and user_engagement, plus app lifecycle events such as first_open and app_update. Google maintains the list in its Help Center. These exist so every property has a baseline of session and lifecycle data regardless of how much custom instrumentation you add.
Three tiers, not one
GA4 events fall into tiers: automatically collected (default, no setup), enhanced measurement (web interactions you switch on like scrolls and outbound clicks), and recommended/custom events you implement. The common error is treating all events as something you must send — re-instrumenting session_start, for example, creates duplicates. Map each event you care about to its tier before adding code.
- Automatic: logged by default, e.g. first_visit, session_start
- Enhanced measurement: toggled web interactions
- Recommended/custom: events you implement yourself
How it appears in analytics and logs
Seeing first_visit or session_start you never coded is normal — they are automatically collected; a custom copy of one would double-count.
Diagnostic use case
Avoid duplicating events GA4 already logs by knowing which are automatically collected, and rely on them for baseline session and lifecycle reporting.
What WebmasterID can help detect
WebmasterID's first-party model emits its own baseline signals; the GA4 automatic-event taxonomy is documented here for comparison and migration.
Common mistakes
- Re-instrumenting an automatically collected event and double-counting.
- Confusing automatic events with enhanced measurement.
- Assuming automatic events bypass consent settings.
Privacy and accuracy notes
Automatically collected events still follow your consent and data settings. Being automatic does not make them exempt; configure collection responsibly. This is educational, not legal advice.
Related pages
- Enhanced measurement (auto events)
Enhanced measurement is a GA4 setting that automatically collects a set of interaction events — scrolls, outbound clicks, site search, video engagement, file downloads, and form interactions — without extra code. It is convenient but not magic: it only covers standard patterns, can over- or under-count, and each option can be toggled. This page explains what it does and its limits.
- Recommended vs custom events
GA4 events come in three tiers: automatically collected, recommended, and custom. Automatic events fire without setup; recommended events have Google-defined names and parameters that unlock standard reports; custom events are ones you invent. The practical rule is to prefer a recommended name whenever one fits, because custom names miss out on prebuilt dimensions, reports, and predictive features.
- Automatic vs manual events in GA4
GA4 events come in tiers by how much you do to get them: automatically collected events need no setup, enhanced-measurement events are toggled on per stream, recommended events you send manually using predefined names, and custom events you both name and send. Knowing which tier an event belongs to tells you whether it needs code, a toggle, or nothing — and prevents duplicate or missing events.
- Events reference (docs)
Which signals WebmasterID emits by default.
Sources and verification notes
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.