Analytics installed after launch means every early visitor — often the highest-intent traffic, from a launch announcement or press mention — goes completely unmeasured. There's no way to retroactively recover that data once the moment has passed. Setting up tracking is a pre-launch task, not a "get to it in week one" task.

GA4 setup checklist

  • A GA4 property is created and a data stream is connected to the live domain (not a staging or development URL).
  • The measurement ID is installed on every page of the site, not just the homepage — a partial install is one of the most common tracking gaps, especially on sites with pages built outside the main template.
  • Tracking is verified live using GA4's Realtime report or DebugView while browsing the site in a separate tab, confirming pageviews and events actually register.
  • Internal traffic (the site owner's own visits, and any agency/dev team testing) is filtered out using an internal traffic filter, so launch-week analytics aren't skewed by the people building the site.
  • Cross-domain tracking is configured if checkout, booking, or any part of the funnel happens on a separate domain or subdomain.

Tag manager checklist

  • The tag manager container (Google Tag Manager or equivalent) is installed in both the <head> and immediately after the opening <body> tag, per the platform's own installation instructions — skipping the body snippet causes it to work inconsistently for users with slow connections.
  • Tags fire correctly across every page template, not just the one used during setup and testing.
  • No duplicate tags exist from a previous platform or template — duplicate GA4 tags double-count every pageview and event.
  • Tag firing is verified using the tag manager's own preview/debug mode before publishing the container live.

Conversion event checklist

  • The 3-5 actions that actually matter for the business — form submit, purchase, signup, key page view — are defined explicitly as conversion events, not left as generic pageviews.
  • Each conversion event is tested manually to confirm it fires exactly once per real action, not zero times or multiple times.
  • Ecommerce tracking (if applicable) captures transaction value, not just a binary "purchase happened" event — value data is what makes ROI reporting possible later.
  • Conversion events are marked as such inside GA4's own configuration, not just sent as regular events, so they surface correctly in reporting and any connected ad platforms.
CheckHow to VerifyCommon Failure
GA4 installed sitewideCheck Realtime report while browsing multiple page templatesMeasurement ID missing from pages built outside the main template
Tag manager firing correctlyUse the platform's preview/debug mode before publishingContainer published without ever being tested in preview mode
Conversion events accurateTrigger each event manually, confirm it appears onceEvent fires on every page load instead of only on the real action
Internal traffic filteredCheck that the dev/agency team's own visits are excludedLaunch-week data skewed by the people building the site

This setup work overlaps directly with a broader conversion tracking validation pass — the difference at launch is timing: none of this can be "fixed later" for the traffic that already happened. Get the events right before the first real visitor arrives.

FAQ

How do I confirm GA4 is actually tracking correctly?

Open GA4's Realtime report, browse the live site in a separate tab, and confirm your own visit and any test events (form submits, button clicks) appear within a minute or two — DebugView gives an even more detailed, event-by-event view for confirming parameters are captured correctly.

  • Realtime confirms basic tracking is alive; DebugView confirms individual event parameters are being captured correctly, which matters for conversion accuracy.
  • Test from a separate device or incognito window so your own regular browsing habits don't muddy the test.

What conversion events should be set up before launch, not after?

The 3-5 actions that actually indicate business value — typically a form submission, a purchase or checkout completion, an account signup, and any key page view like a pricing page — should be defined and tested before traffic arrives, because GA4 can't retroactively reconstruct conversion data for traffic it wasn't configured to measure.

  • Picking too many conversion events dilutes reporting; 3-5 genuinely decision-relevant actions is usually the right range.
  • Ecommerce events should capture transaction value, not just a yes/no purchase flag, to make ROI reporting possible.