Google Analytics Test
The Google Analytics Test detects every analytics tag on any URL — Google Analytics 4 (GA4), Universal Analytics (legacy), Google Tag Manager, plus other major analytics vendors (Adobe, Mixpanel, PostHog, Plausible, Fathom). We verify each tag is loading correctly, fires the expected pageview, and flag duplicate or conflicting installs that distort your data. Bad analytics installs silently produce wrong numbers — by the time you notice, weeks of decisions have been made on noise.
What This Tool Checks
- Google Analytics 4 (gtag / GA4 measurement ID)
- Google Tag Manager container ID
- Universal Analytics (legacy ga.js / analytics.js)
- Other analytics vendors (Adobe, Mixpanel, etc.)
- Duplicate / conflicting installs
- Tag firing on pageview
- Data layer presence and structure
Why It Matters for SEO
Analytics is the foundation of every data-driven decision. A broken or duplicated install distorts every metric you act on — bounce rate, conversion, revenue per visit. The most common installation bugs (double counting due to two installs, missing pages because the tag is in the wrong template, sessions broken by referrer exclusion) are silent until someone runs an audit. This tool surfaces them in seconds.
How to Fix It
Standardise on a single tag manager (GTM is the safe default) and remove every hard-coded duplicate. Use one GA4 property per business with a clear naming convention. Configure cross-domain tracking via gtag's linker. Migrate any remaining Universal Analytics installs to GA4. Re-test on every important template after changes.
How It Works
Headless Chrome loads the page, captures every script that matches known analytics patterns, and inspects the global window namespace for analytics objects (gtag, dataLayer, _gaq, etc.). Tag firing is verified by capturing the network request to the relevant collection endpoint.
Common Mistakes to Avoid
- Both GA4 and Universal Analytics still firing (double-counts everything)
- Tag installed via two paths (GTM and hard-coded) doubling sessions
- Tag missing from one template (under-reporting traffic)
- Cross-domain tracking mis-configured (sessions broken on every domain hop)
- Forgetting to migrate from Universal Analytics (sunset July 2024)
Quick Checklist
- Exactly one GA4 install per page
- No remaining Universal Analytics tags
- GTM is the single source of truth for marketing tags
- Pageview fires on every important template
- Cross-domain tracking configured if applicable