Setting up key events in GA4 and conversions in Google Ads

Google renamed GA4 conversions to GA4 key events, which confused a lot of people who had just learned the old wording. The mechanics did not change much: you record an event, mark it as important, and optionally send it to Google Ads so your campaigns can be judged on outcomes instead of clicks. This walkthrough covers that sequence, the double-counting traps, and how to verify each step before trusting a single report.

Google adjusts menu names and screen layouts in both products regularly, so treat the navigation described here as approximate. Look for the concept if the exact label differs in your account.

Step one: make sure the event exists before you mark anything

You cannot mark an event as important until GA4 has seen it at least once. So the first job is always getting the event to fire.

GA4 collects some events automatically, and enhanced measurement adds more, such as outbound clicks, file downloads and site search. Check what you already have in the admin area under the data stream settings before building anything custom.

Three ways to create the event you need

• Enhanced measurement: free and instant, but the event names are generic and you often need parameters to tell one button from another.
• Google Tag Manager: the usual choice. A trigger detects the action, and a GA4 event tag sends a name you decide.
• Direct gtag calls in code: useful when a developer controls the form or checkout logic and can fire the event only on genuine success.

Name events so the report reads itself

Use lowercase with underscores, keep names short, and make them descriptive without being page-specific: generate_lead, whatsapp_click, quote_request, brochure_download. Put the varying details in parameters such as form_location or page_path rather than inventing a separate event name for every page. Naming is much harder to fix later than it is to get right now.

Step two: mark the event as a key event

In the GA4 admin, open the events list for the property. Each event row has a toggle that marks it as a key event. Turn it on only for actions that genuinely matter, usually two to five in total.

If the event has not fired yet, most GA4 versions let you create a key event by typing the exact event name in advance. Spelling must match exactly, including case.

Two points that catch people out. First, marking an event does not backfill history — reporting starts from that moment. Second, GA4 counts key events by default every time they occur, so an event that can fire twice in one session will be counted twice.

Step three: import key events into Google Ads

To let Google Ads optimise towards real outcomes, link the accounts and import the key event.

1. In GA4 admin, link the property to the Google Ads account. You need edit access to the GA4 property and admin access in Ads.
2. In Google Ads, open the conversions area under goals or measurement and choose to import from Google Analytics 4 properties.
3. Select only the key events you want Ads to optimise towards.
4. Set the conversion action's category, counting method and attribution settings.
5. Wait — imported conversions can take up to 24 hours or so to start showing data.

For the counting method, choose one for leads and enquiries, where a single customer contacting you twice is still one lead, and every for purchases, where two separate orders are genuinely two conversions.

Also decide which conversions count as primary. Only primary actions feed bidding. Keep supporting signals such as brochure downloads as secondary so they are visible without steering your budget.

Avoiding double counting, the most common failure

Double counting quietly inflates results and, worse, teaches automated bidding the wrong lesson. Check for these five situations:

• The same action tracked twice in GA4. A thank-you page view marked as a key event plus a form-submit event both firing.
• Two measurement systems in Ads. A Google Ads conversion tag on the thank-you page and the imported GA4 key event for the same action. Pick one as primary.
• A tag firing on every page view. Usually caused by a trigger set to All Pages instead of a specific URL or event.
• Thank-you page refreshes. If someone reloads or bookmarks it, the conversion records again. Either fire on a genuine submit event, or use a counting method of one.
• Duplicate GA4 tags. Two installations of the same measurement ID double everything, not only conversions.

A quick sanity test: compare the number of key events recorded yesterday with the number of real enquiries in your inbox or CRM. If GA4 says 14 and you received seven, you have found your problem.

Testing with DebugView before you trust anything

DebugView, found in the GA4 admin section, shows events arriving from a single debug-enabled device in near real time. It is the fastest way to confirm reality matches intention.

1. Enable debug mode: use Google Tag Manager's preview mode, or the official Google Analytics Debugger extension for Chrome.
2. Open DebugView in GA4 and select your device in the debug device list.
3. Perform the action on your site — submit the form, click the WhatsApp button.
4. Watch the event appear in the timeline. Click it to inspect parameters.
5. Confirm the event fires exactly once, with the correct name and parameters.
6. Repeat on a real phone, not just a resized desktop browser, because mobile forms often behave differently.

Then wait a day and cross-check the standard reports, since DebugView proves the event was sent but not that it was attributed the way you expect.

Get one event right, then repeat the pattern

Pick your single most valuable action, take it through all five stages — fire, name, mark, import, verify — and only then add the next. If the tracking sits on top of a form or checkout that needs fixing first, our team can sort both together as part of your website development work.

Frequently asked questions

Is a key event the same as an old GA4 conversion?

Functionally yes. Google changed the wording so that "conversion" refers mainly to what Google Ads counts, while GA4 reports on key events. Existing setups kept working through the rename.

How many key events should a small business mark?

Usually two to five. Marking too many makes every session look like a success and makes reports harder to read at a glance.

Why do Google Ads and GA4 show different conversion counts?

They use different attribution models, time windows and counting rules. Ads often credits a conversion to the date of the ad click, while GA4 reports it on the date it happened. Some difference is expected.

Do I still need a Google Ads conversion tag if I import from GA4?

Not for the same action — that is exactly how double counting starts. Many advertisers do keep a direct Ads tag for purchases because of reporting speed, but then they exclude the imported version from bidding.