Guide 187 · Conversions · GA4 + Tag Manager
Key event for outbound link clicks in GA4: outbound_click, the partner link, and the rate
Enhanced measurement sends outbound_click whenever a visitor clicks a link that leaves the site, and the link_url parameter says where they went. Marking outbound_click itself makes every exit a key event, which is rarely the point. This guide marks it for a resource page where the outbound link is the outcome, and works out the click rate for a week.
After the steps, the outbound_click key event appears under the Key events tab in Admin, and the standard reports show it within a day. The worked example below gives the count and the rate to expect.
Download the reference: the outbound_click key-event reference (JSON) (719 bytes, MD5 dc128a175994340263f6934940925d81). It holds the event name, the counting method, the worked-example figures recomputed for this guide, and the checkpoints that prove the key event is recording. The figures in the file are the same figures shown on this page.
What you need
- Editor access or above at property level in GA4. Marking an event as a key event is a property setting, and the star in the Events table does not appear for a Viewer.
- Enhanced measurement enabled in the web data stream, so outbound_click is collected. The event fires on clicks to links that lead away from the site.
- A page where leaving the site is the outcome. In this guide the page is a partner directory, and the outbound link is the product.
The trace
- Confirm outbound_click is collecting. Open Reports, then Engagement, then Events, and find the outbound_click row. If it is missing, enhanced measurement is off in the data stream, or no visitor has clicked an outbound link yet.
- Check the link_url parameter in DebugView. Open Admin, then Data display, then DebugView, click a partner link, and watch outbound_click arrive with link_url set to the partner address. The parameter is what separates one destination from another.
- Decide whether to mark outbound_click or build a narrower event. If every outbound link on the page is a partner link that matters, mark outbound_click. If only one partner matters, build a new event from outbound_click with a link_url condition first, as the create-key-event guide shows, and mark that instead. This guide marks outbound_click.
- Mark outbound_click as a key event. Open Admin, then Data display, then Events, and click the star on the outbound_click row. A standard property can mark up to 30 events, and this is one of them.
- Read the click count in the Events report. In the worked example the week shows 203 outbound_click events, of which 148 go to the main partner and 55 go to other sites. Marking outbound_click counts all 203 as key events, which is why the narrower event exists for pages where only one link matters.
- Work out the session key event rate. The week shows 1,700 sessions and 176 sessions with an outbound_click key event, which is 176 / 1,700 = 10.35%. The 203 events came from 176 sessions, so 27 sessions clicked out more than once.
Dead ends
DEAD END — MARKING outbound_click ON A SITE FULL OF SOCIAL ICONS. Every click on a social icon, a footer link, and a source citation becomes a key event, and the rate describes the footer rather than the partner page. Build the narrow event for the one link that matters.
DEAD END — READING THE COUNT AS UNIQUE VISITORS. The 203 events are clicks, not people. One visitor who clicks three partner links counts three times under once per event. Use sessions with a key event, 176 here, when the question is how many visits clicked out.
DEAD END — EXPECTING outbound_click ON AN INTERNAL LINK. The event only fires for links that lead away from the site. A link to another page on the same site fires a page_view, not an outbound_click, and marking outbound_click will never count it.
End state
The outbound_click event is a key event on this page, where the outbound link is the product. The week closes at 203 key events from 176 sessions, a session key event rate of 10.35%.
| Figure | Value |
|---|---|
| Sessions in the week | 1,700 |
| outbound_click key events | 203 |
| Clicks to the main partner | 148 |
| Clicks to other sites | 55 |
| Sessions with an outbound_click key event | 176 |
| Session key event rate | 10.35% |
The rate is 176 / 1,700 = 10.35%, recomputed in Python 3 and rounded to two places. The click split adds up: 148 + 55 = 203. The figures are a worked example, not a real property.
Sources
- Analytics Help — [GA4] Recommended events — the recommended event names, including generate_lead, sign_up, and purchase
- Analytics Help — About key events — marking an event as a key event, the 30-event limit for a standard property, and 50 for Analytics 360
- Analytics Help — Monitor events in DebugView — watching events with their parameters in DebugView
Checked 11 November 2026. The click paths above are the ones in Google's help pages, read 11 November 2026. The outbound_click event is an enhanced measurement event with a link_url parameter, and marking it from Admin, then Data display, then Events, are as Google documents them. No step in this guide was run inside a live Analytics property, because Admin needs a Google sign-in and this site does not sign in as anyone. The figures on this page are a worked example recomputed in Python 3 with decimal arithmetic, not numbers from a real property. Google moves menu items without warning; if a path on this page no longer matches, the linked help page is the current map.