Google Analytics 4 and Conversion Tracking: How to Truly Measure Your Website's Performance
A website that does not measure conversions is like a shop without a till: people walk in, some buy, but nobody knows how many or why. Google Analytics 4 (GA4) is now the standard for measuring user behaviour, but badly configured it only produces impressive, useless numbers. This guide explains how to set up reliable conversion tracking on websites and landing pages, in compliance with GDPR.
What GA4 Is and Why It Differs from Universal Analytics
Google Analytics 4 is Google's web analytics platform built on an event-based model: every user interaction — page view, click, scroll, form submission — is an event, and sessions and pageviews are no longer the primary unit of measurement. This model unifies website and app data and follows the full user journey.
For an SME the practical difference is that in GA4 nothing beyond basic events is measured automatically: conversions — quote requests, sign-ups, phone calls, purchases — must be explicitly defined as key events. Without that configuration GA4 shows traffic but no business results.
Which Conversions to Track on a Business Website
The rule is to track a few actions tied to real economic value, separating macro-conversions (quote request, purchase, booking) from micro-conversions (guide download, phone number click, newsletter sign-up) that signal growing interest.
- Contact or quote request form submission (generate_lead event)
- Clicks on phone number, email and WhatsApp button
- Downloads of documents, price lists and case studies
- Newsletter sign-ups
- Completed purchases or bookings, with value and currency
- Scroll beyond 75% and time on page for in-depth landing pages
Google Tag Manager: The Right Layer for Managing Tracking
Google Tag Manager (GTM) is the container that lets you add and change measurement tags without touching site code each time. You install it once and manage GA4 events, ad pixels and Google Ads conversions from a versioned, testable environment.
A good setup relies on a consistent data layer: the site tells GTM what happened — for example 'form_submitted' with the type of service requested — and GTM decides which tools to notify. This avoids duplicate events and makes tracking resilient to redesigns.
Consent and GDPR: Consent Mode v2 Without Losing All Your Data
In Europe tracking requires user consent. Consent Mode v2 is how the cookie banner tells Google the consent state: if the user declines, tags adapt and Google can estimate missing conversions through statistical modelling instead of losing measurement entirely.
To be compliant you need a banner that blocks tags until a choice is made, correctly configured consent signals (analytics_storage, ad_storage, ad_user_data, ad_personalization) and an up-to-date cookie policy. For anyone advertising on Google, Consent Mode v2 is effectively mandatory to keep remarketing and measurement in the EEA.
From Data to Decisions: What to Review Every Month
The most common risk is metric overload. An SME needs only a few indicators read regularly: conversion rate by channel and landing page, cost per lead if you advertise, entry pages that bring the most contacts, and form drop-off points. Month-over-month comparison matters more than any absolute value.
Connecting GA4 to Looker Studio gives an automatic report that non-analysts can read, and lets you cross-reference CRM data to see which channels produce not just leads but real customers.
Frequently Asked Questions About GA4 and Conversions
Do I need GA4 if I already have Google Search Console?
Yes: Search Console measures visibility on Google (impressions, clicks, positions), while GA4 measures what users do after arriving on the site. They complement each other and can be linked.
How long does a correct setup take?
For a business website with 3-5 conversions to track, a complete setup with GTM, events and Consent Mode typically takes one to three days of work, testing included.
How do I check conversions are recorded correctly?
Use GA4 DebugView and Tag Manager preview to watch events in real time, then compare GA4 conversions with the requests actually received by email or CRM for a couple of weeks.