How to Set Up GA4 Conversion Tracking (Key Events)
In GA4, conversions are called key events. To track them, install the Google tag or Google Tag Manager, send an event for each valuable action (such as generate_lead when a form is submitted), then mark that event as a key event under Admin, Data display, Events. Test with DebugView before relying on the data, set data retention to 14 months, and link Google Ads so you can import key events as ad conversions.
- Google renamed GA4 conversions to key events in 2024; Google Ads still uses the word conversions.
- Standard GA4 properties allow up to 30 key events, so mark only actions that matter to the business.
- Track the confirmed outcome (a successful submission) rather than a button click.
- Always verify new events in DebugView or Tag Assistant before trusting the reports.
- Default data retention is short; raise it to 14 months for year-over-year analysis.
The Steps
- List the actions that make moneyWrite down the three to six actions that signal a real lead or sale: form submissions, calls, bookings, purchases, quote requests. Ignore vanity actions like scrolling unless they truly predict revenue.
- Install the Google tag or GTMAdd the GA4 Google tag to every page, or install Google Tag Manager and create a Google tag with your measurement ID. Use one method, not both, to avoid double counting.
- Review enhanced measurementIn the web data stream settings, check which automatic events are on. Built-in form interaction tracking is often unreliable, so plan to replace it with a dedicated event for important forms.
- Send an event for each actionFire a recommended event such as generate_lead or purchase when the action is confirmed: a thank-you page load, a form success message, or a callback from your booking or checkout tool.
- Mark the events as key eventsIn Admin, Data display, Events, click the star next to each event once it has been received, or create a new event with the key event toggle on, and choose a value and counting method.
- Test in DebugViewUse Tag Assistant or GTM preview mode, complete each action yourself, and confirm the event and its parameters appear correctly in DebugView. Fix duplicates before going live.
- Raise data retention and link Google AdsSet event data retention to 14 months, link your Google Ads account, and import the key events you want ad campaigns to optimize toward.
- Add campaign tagging and consentTag ad, email and social links with UTM parameters, and implement consent mode if you serve visitors in regions that require consent for analytics or advertising cookies.
Key Events, Conversions and Why the Names Changed
In 2024 Google renamed GA4 "conversions" to key events. The idea is that a key event is any event you flag as important inside Analytics, while a conversion is now the term used in Google Ads for actions that ad bidding optimizes toward. You can create Google Ads conversions from GA4 key events, but they are managed in two places: settings like counting method for ads live in Google Ads.
The practical point for a business owner: GA4 records everything as events. Nothing counts as a lead until you tell GA4 which events matter. Standard properties allow up to 30 key events, which is plenty if you are disciplined.
When you mark a key event you also choose a counting method and, optionally, a default value. "Once per session" suits lead forms, because one person submitting twice is still one lead. "Every event" suits purchases. A rough value per lead (for example, average deal size multiplied by your close rate) lets reports compare channels by estimated revenue instead of raw counts.
Choosing What to Track
Most small and mid-sized businesses need only a short list:
- generate_lead: contact, quote or consultation form submitted successfully.
- Phone call clicks: taps on a
tel:link on mobile, plus calls from a call-tracking tool if you use one. - Booking completed: confirmed appointment from your scheduler.
- purchase: for ecommerce, with value, currency and transaction ID.
Using Google's recommended event names (such as generate_lead and purchase) makes reports and future features work better than custom names. Avoid marking page views of the contact page or clicks on a submit button as key events. Both inflate the numbers: people view the page without filling it in, and people click submit on forms that then fail validation.
Tracking Forms and Calls Reliably
Forms cause most tracking problems. The most reliable options, in order:
- Thank-you page: redirect to a unique confirmation URL after a successful submission and fire the event on that page. Simple and robust.
- Success callback: many form tools push a
dataLayerevent or expose a JavaScript callback on success. Trigger your GTM tag from it. - Element visibility: fire when the success message appears. Works, but breaks when the message text or design changes.
Embedded forms in iframes from third-party tools usually cannot be seen by your site's tag at all. Check whether the vendor offers a native GA4 integration or a redirect option. For calls, a tap on a tel: link shows intent, not a completed call. If phone leads are a large share of revenue, a call-tracking service that reports qualified calls back to GA4 or Google Ads gives a far truer picture.
Testing and Common Pitfalls
Never trust a new event until you have watched it arrive. Open Tag Assistant or GTM preview, complete the action yourself and check DebugView: the event should fire exactly once with the right parameters. Common faults include:
- Double tagging: the Google tag hard-coded in the theme and also fired by GTM, so every event counts twice.
- Counting every reload: a thank-you page that fires again when refreshed. GA4's "once per session" counting option for key events reduces this.
- Internal traffic: staff testing forms. Define internal traffic by IP in the data stream and set the filter to active.
- Short retention: GA4's default event data retention is short. Change it to 14 months under Admin, Data collection and modification, Data retention.
If you see key events in GA4 but fewer conversions in Google Ads, that is normal. The two systems use different attribution and count only the conversions tied to ad clicks in Ads. The GA4 vs Search Console comparison explains how analytics data differs from search data.
Connecting Tracking to Real Revenue
Key events tell you which channels produce leads, not which produce customers. To close that gap, store the source of each lead in your CRM (UTM parameters and the Google click ID can be captured in hidden form fields), then mark leads as qualified or won. Google Ads can import those offline outcomes so campaigns optimize for sales rather than form fills. That is the foundation for measuring marketing ROI properly.
Finally, consider privacy. If you have visitors from regions that require consent for analytics or ad cookies, use a consent banner that supports Google's consent mode so tags adjust their behavior to each visitor's choice. Review the requirements that apply to you with a qualified advisor.
Sources and Further Reading
We link to the primary documentation so you can verify the details yourself.
- Mark events as key events, Google Analytics Help
- Recommended events, Google Analytics Help
- Monitor events in DebugView, Google Analytics Help
- Data retention, Google Analytics Help
- Consent mode on websites and mobile apps, Google Analytics Help
Related Questions
What is the difference between a GA4 key event and a Google Ads conversion?
A key event is an event you mark as important in Google Analytics. A conversion is an action Google Ads uses for reporting and bidding. You can import GA4 key events into Google Ads as conversions, but each system applies its own attribution and settings.
Why does GA4 show more leads than my CRM?
Usually because the event fires more than once (page refreshes, double tagging), fires on attempts rather than successful submissions, or counts spam submissions. Test the event in DebugView, switch to once-per-session counting and add spam protection to the form.
Should I use Google Tag Manager or the plain Google tag?
If you only need GA4 with one or two events, the Google tag is fine. If you track several forms, calls and ad pixels, Google Tag Manager is easier to maintain because changes do not require editing the website code.
How long until key events show up in reports?
Events appear in DebugView and Realtime within seconds. Standard reports can take up to a day or two to process. After marking an existing event as a key event, only data from that point forward counts as key events.