The ad_click event
ad_click represents a user interacting with a served advertisement. In GA4's model it is the click counterpart to ad_impression for third-party ad inventory, just as select_promotion pairs with view_promotion for internal merchandising. This page clarifies which click event belongs where so you do not conflate paid ad interactions with on-site promotion clicks or generic outbound link clicks.
What this means
ad_click captures interaction with an advertisement that was served to the user. The important distinction is intent and inventory: ad_click is for third-party ads, select_promotion is for your own promotional creatives, and the generic click event is for arbitrary element interactions.
Keeping these separate prevents double counting and keeps ad analysis isolated from on-site engagement analysis.
Choosing the right click event
Use ad_impression/ad_click for served ad inventory, view_promotion/select_promotion for internal banners, and outbound_click for links leaving your site. Each pairing answers a different question, and mixing them produces misleading funnels. Where the precise documented parameter list for ad_click is uncertain for a given platform, treat platform docs as authoritative.
Data not yet verified: exact ad_click parameter schema varies by serving platform and SDK version.
- ad_click: served third-party ad interaction
- select_promotion: internal promotion click
- outbound_click: link to another domain
How it appears in analytics and logs
An ad_click event means a user interacted with a served ad. Reading it apart from select_promotion and click keeps ad performance separate from on-site engagement.
Diagnostic use case
Distinguish clicks on served ads from clicks on internal promotions and outbound links so each is measured with the right event.
What WebmasterID can help detect
WebmasterID records outbound and CTA clicks first-party; ad_click shows how GA4 keeps served-ad interactions in their own event lane.
Common mistakes
- Logging internal banner clicks as ad_click.
- Counting ad_click and outbound_click for the same interaction.
- Assuming the same parameters across every ad platform.
Privacy and accuracy notes
Ad-click parameters describe the placement, not the person. Avoid passing identifiers that could link the click to an individual. Educational, not legal advice.
Related pages
- The ad_impression event
ad_impression is a GA4 event used to record that an ad was shown, most commonly in mobile apps monetised through ad mediation. It can carry ad_platform, ad_source, ad_format, ad_unit_name, and a value/currency representing estimated revenue. It is distinct from internal view_promotion: ad_impression is about third-party ad inventory served in your app, not your own merchandising slots.
- The select_promotion event
select_promotion is the click counterpart to view_promotion in GA4's recommended e-commerce set. You fire it when a user interacts with an internal promotional banner or slot. It carries promotion_id, promotion_name, creative_name, creative_slot, and items so you can join clicks back to impressions and read which on-site placements drive engagement with featured products.
- The outbound click event
An outbound click event fires when a visitor clicks a link that leads to a different domain than the current site. GA4 records it as a click event with an outbound parameter when enhanced measurement is on. It tells you where your pages send people — partners, references, social profiles — which is useful for understanding exit paths but says nothing about what happens on the destination.
- CTA tracking
Separate ad, promotion, and outbound clicks.
Sources and verification notes
- Google — GA4 events referencead_click context; exact schema is platform-dependent.
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.