Setting up GA4 conversion tracking properly

GA4 will happily collect data the moment you install it and tell you almost nothing useful. The default setup measures page views and calls it analytics.

Here's what turns it into something you can make decisions with.

1. Install it once, properly

One installation method. Either the gtag snippet or Google Tag Manager — not both.

Double installation is the most common cause of inflated numbers, and it's easy to create accidentally when a theme includes a GA4 field and you also add a tag manually.

Check: use Google Tag Assistant and confirm exactly one GA4 tag fires per page.

2. Decide what a conversion actually is

Before touching the interface, write down the two or three actions that genuinely represent value. Form submission. Purchase. Booking. Phone call.

Not: newsletter signup and page view and scroll depth and video play. Enhanced measurement will happily mark half a dozen things as key events, and every one you add dilutes the signal you send to ad platforms.

Two or three key events. That's it.

3. Set up events that reflect reality

The default form_submit event fires on form interaction patterns that don't always mean a submission happened, and misses forms that submit via JavaScript without a page change — which is most modern forms.

Better: fire a custom event on actual submission success. If your form redirects to a thank-you page, trigger on that page. If it submits via AJAX, fire the event in the success callback.

Then mark that custom event as a key event.

4. Pass values where you can

For e-commerce, pass actual transaction value. For lead gen, pass an estimated value per lead type if you have one — a demo request and a newsletter signup are not worth the same, and treating them equally makes every downstream number meaningless.

Value data is what makes value-based bidding possible later.

5. Link everything

• Google Ads — enables conversion import and audience sharing
• Search Console — brings organic query data into GA4
• Merchant Center, if e-commerce

These take minutes and most accounts skip at least one.

6. Filter internal traffic

Your own visits, your developer's visits, your agency's visits. On a low-traffic site these materially distort behavioural metrics.

Define internal traffic by IP in Admin → Data Streams, and make sure the filter is set to Active rather than Testing. Leaving it in testing mode is a classic.

7. Set data retention to the maximum

Default is 2 months. Change it to 14. There's no reason not to, and you'll want the history the moment you need to compare year on year.

8. Build the three reports you'll actually check

Skip the default reports. Create explorations for:

1. Conversions by channel — where results come from
2. Landing page performance — entry point, sessions, conversion rate
3. Conversion paths — how many touches before conversion

Everything else is curiosity.

9. Reconcile monthly

GA4 will not match your ad platforms, and it will not match your back end. That's normal — different attribution models, different windows, different definitions.

What matters is knowing the size of each gap so you can interpret the numbers. An unreconciled analytics setup produces confident, wrong decisions.

The order matters

Install → define conversions → build real events → pass values → link accounts → filter internal → extend retention → build reports → reconcile.

Doing this out of order means rebuilding. Doing it properly once takes an afternoon and pays for itself the first time you avoid cutting a campaign that was actually working.