Google Analytics 4
Google Analytics 4 is the standard tool for measuring traffic, audience behaviour, and conversions — without it, every design and marketing decision is made without evidence.
Where it comes from
Google Analytics began in 2005, when Google acquired a web-statistics company called Urchin and made its tool free to almost anyone with a website. The version most sites run today — Google Analytics 4 — replaced the older Universal Analytics in 2023, rebuilt around individual events rather than page-and-session counts.
Why it matters for your website
A website without analytics is operating entirely on assumption. You do not know how many people visit, where they come from, what device they use, how long they stay, or whether they reach the actions that matter. That makes it impossible to know which acquisition channels are worth investing in, which pages are losing visitors, or whether a change you made improved or worsened results. GA4 replaced Universal Analytics in 2023 and is free for the vast majority of sites. The absence of analytics doesn't just leave a gap in reporting — it means every optimisation effort is untethered from evidence. Legacy Universal Analytics tags (analytics.js) stopped collecting data in July 2023 and are functionally dead, even though their presence can give a false impression that measurement is running.
The trap isn't only having no analytics — it's having analytics that quietly stopped working. Universal Analytics stopped collecting data in July 2023, but its old tracking tag still sits in the page on thousands of sites, giving owners a false sense that measurement is running when the numbers behind it are frozen.
Traffic you can't measure can't be grown with confidence. Without a baseline you can't tell whether a redesign helped or hurt, or which channel is actually paying its way — so spend follows hunches instead of evidence.
Wrong vs right
A business runs Google Ads for six months and increases spend because "the site is getting more traffic." With no analytics, they can't see whether that traffic converts or where it drops off — they're paying for activity they can't measure.
The same business has GA4 with a conversion event on the contact form. They can see which campaigns drive completions, which pages lose people before the form, and that mobile converts at half the desktop rate — a clear signal of where to look next.
An old site still loads analytics.js from a 2019 build. A dashboard reads from it and shows a flat line nobody questions — because the tag is technically "present."
The legacy tag is removed and a GA4 property with a valid G-XXXXXXXXXX Measurement ID is installed, with one conversion event configured so the site measures outcomes, not just visits.
Understanding Google Analytics 4
Analytics answers the most basic questions a site owner has — how many people came, where from, on what device, and whether they did the thing you wanted — and it answers them with evidence instead of opinion. GA4 is the default because it is free for almost every site, integrates with the rest of Google's tools, and has become the shared reference point that most guidance assumes you have.
The single most important configuration step is also the one most often skipped: setting up at least one conversion event. Raw traffic counts are interesting but rarely actionable; the moment you tell GA4 what a "win" looks like — a form submit, a booking, a key page reached — every other report gains a purpose, because you can finally connect a source, a page, or a device to an outcome.
You usually don't need a developer. Most platforms — WordPress, Squarespace, Wix, Shopify — have a built-in field for a Measurement ID. Google Tag Manager is worth the small extra setup only if you expect to add several tracking tags over time, because it lets you manage them in one place without editing the site for each one.
How Kweri checks it
Kweri looks for a working GA4 tag during the page analysis: the gtag.js script, a valid Measurement ID in the expected G-XXXXXXXXXX format, and signs that the tag is correctly initialised. It separately detects legacy Universal Analytics (analytics.js) and flags it as non-functional, since it has collected nothing since July 2023. It notes Google Tag Manager when present but doesn't treat that as proof GA4 is configured inside it — GTM can be installed with no analytics wired up at all. What Kweri can't see is whether you actually review the data; that part is on you.
FAQ
Is GA4 free?
Yes, for the vast majority of websites. Google Analytics 4 is free with no session or traffic limits. There's a paid enterprise tier (Analytics 360) with extra features, but the standard product is what most sites need.
What's the difference between GA4 and Universal Analytics?
Universal Analytics was the previous version. Google stopped collecting UA data in July 2023, so sites still running the old analytics.js tag are recording nothing. GA4 uses a different, event-based data model and needs its own implementation even if UA was there before.
Do I need a developer to install GA4?
Usually not. Most website platforms have a built-in integration where you paste a Measurement ID, no code required. Google Tag Manager is worth it if you expect to add several tracking tags over time, as it centralises tag management.
How do I know if my analytics is actually working?
Check that a valid Measurement ID (G-XXXXXXXXXX) is present, that the tag loads before the closing </head>, and that real-time reports register your own visit. If a consent banner is in place, confirm it's configured to allow analytics once consent is given — otherwise the tag may be blocked.
Related principles
Session recording tools capture how real users behave — where they click, how far they scroll, where they hesitate — the qualitative layer that quantitative analytics alone cannot provide.
Traffic source analysis reveals where your visitors come from — organic search, paid, social, direct, or referral — the foundational layer for knowing which acquisition channels are worth investing in.
Device and viewport analytics reveal whether your users are primarily on mobile or desktop, and at what screen widths — directly informing which experience to prioritise.
Exit rate identifies the pages where users most frequently leave your site — the starting point for diagnosing where you are losing people who might otherwise have converted.
Heatmaps aggregate where users click, how far they scroll, and where their attention concentrates — making invisible user behaviour visible at a glance.
Attribution & sources
Identified by Google (2005 (GA4 from 2023)). Catalogued from Google Analytics developer documentation.
Google Analytics originated with Google's 2005 acquisition of Urchin; GA4 replaced Universal Analytics as the standard implementation in 2023. Setup is documented at analytics.google.com and developers.google.com/analytics.
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