Your GA4 is 'working.'
That's not the same as accurate.

Events are firing. Reports are generating. Traffic numbers exist. Everyone assumes the data is fine. It's probably not.

Most GA4 implementations look functional on the surface but are quietly corrupted underneath. Duplicate events inflating conversions. Inconsistent naming turning one action into three separate metrics. Consent misconfiguration leaking data you shouldn't be collecting - or blocking data you actually need. Cross-domain tracking splitting single user journeys into phantom sessions.

We audit GA4 implementations the way an engineer inspects infrastructure - systematically, technically, and without assuming anything is working until we've verified it ourselves.

Request a GA4 Audit

The problems hiding in plain sight.

GA4 doesn't fail loudly. It fails quietly - still collecting data, still generating reports, still giving you numbers. Just the wrong ones.

Duplicate events are the default, not the exception.

Your CMS injects GA4 natively. GTM also fires GA4. Enhanced Measurement adds its own layer. Now every page_view fires twice, every scroll fires twice, and your engagement metrics are inflated by 40-100%. Nobody notices because the numbers look "healthy."

Event naming is a free-for-all.

form_submit, formSubmit, submit_form, contact_form_send - same action, four different events. Your funnel analysis shows drop-offs that don't exist. Your conversion reports undercount because GA4 treats each variant as a separate metric. One naming inconsistency can make an entire funnel invisible.

Conversions aren't aligned with business outcomes.

You're tracking page_view as a conversion because someone ticked a box during setup. Meanwhile the actual business actions - qualified lead submissions, booking confirmations, purchase completions - are either untracked or buried in custom events nobody monitors. Your measurement plan doesn't exist because nobody wrote one.

Cross-domain tracking is silently broken.

Users move between your main site, booking platform, and payment gateway. Without proper cross-domain configuration, GA4 treats each domain hop as a new session with a new user. Your traffic looks 2-3x higher than reality. Your conversion rate looks 2-3x lower. Revenue gets misattributed to referral instead of the campaign that actually drove it.

Consent Mode is either absent or misconfigured.

No Consent Mode means you're collecting data from users who haven't consented - a compliance liability. Misconfigured Consent Mode means you're blocking all measurement for 30-60% of your traffic and getting nothing back, not even the modelled data Google provides when Consent Mode is set up correctly.

UTM discipline has collapsed.

utm_source=Facebook, utm_source=facebook, utm_source=fb, utm_source=meta - same platform, four channel entries. Someone invented utm_source=spring_sale. Your Unassigned channel in GA4 is growing every month and nobody knows why. Campaign performance data is useless because the inputs were never standardised.

What we check, fix, and rebuild.

This isn't a 15-minute scan from an automated tool. It's a technical inspection of your entire measurement stack.

Property and data stream configuration

Data retention settings, Google Signals, Enhanced Measurement toggles, internal traffic filters, referral exclusions, cross-domain setup. The foundational settings that most implementations get wrong on day one and never revisit.

Event taxonomy audit

Every event firing on your site - mapped, categorised, and checked for duplicates, naming conflicts, and parameter inconsistencies. We compare what GTM sends against what GA4 actually receives. The gap is usually larger than anyone expects.

Conversion and key event validation

Are your conversions measuring what you think they're measuring? We validate each conversion event against actual user behaviour, check for double-counting, and verify that the numbers in GA4 match what your CRM or backend reports. If they don't - and they usually don't - we find out why.

GTM container review

Tag firing order, trigger conditions, variable configuration, consent integration. We inspect every tag for conflicts, redundancies, and race conditions. A messy GTM container is the single most common source of bad GA4 data.

Cross-domain and referral configuration

If your users cross domains - payment gateways, booking systems, subdomains - we verify that sessions persist correctly, referral exclusions are set, and linker parameters are passing. Broken cross-domain tracking is invisible in standard reports but devastating to attribution.

Consent Mode and privacy compliance

Consent Mode v2 implementation check. Are tags respecting consent signals? Is modelled data flowing? Are you collecting data you shouldn't be - or blocking data you're legally allowed to collect? We verify the technical implementation against your actual consent banner behaviour.

Attribution and channel grouping integrity

UTM parameter audit. Default channel grouping accuracy. Unassigned traffic investigation. We trace why campaigns end up in the wrong channels and fix the taxonomy so your acquisition reports actually reflect reality.

CRM and backend data reconciliation

We compare GA4 conversion counts against your CRM, payment processor, or backend database. The delta tells us exactly how much data you're losing - and where in the pipeline it disappears. This is where most businesses discover their GA4 has been undercounting by 20-40%.

What you walk away with.

This isn't a PDF that says 'things could be better.' It's an engineering report with specific findings, root causes, and implementation instructions.

Complete data quality assessment

Every issue documented with severity, root cause, and impact on your reporting. Not vague recommendations - specific technical findings you can hand to any developer or agency and say "fix these."

Prioritised fix list

Issues ranked by business impact. Critical data integrity problems first, cosmetic improvements last. You know exactly what to fix in what order - and what you can safely ignore.

Measurement plan

A proper event taxonomy aligned to your business objectives. What to track, how to name it, what parameters to include, and what constitutes a conversion. The document your GA4 should have been built from in the first place.

Implementation support

We don't just hand you a report and disappear. If you want us to implement the fixes directly, we do. GTM changes, GA4 configuration, Consent Mode setup, event restructuring - verified in DebugView before anything goes live.

When does a GA4 audit make sense?

Reports don't match reality.

Your GA4 says 50 conversions. Your CRM says 35. Your payment processor says 42. Nobody can explain the discrepancy, so everyone picks the number that makes their report look best.

You've changed agencies, developers, or teams.

Every handover leaves debris. Tags from the old agency still firing. New tags layered on top. Nobody did a clean audit during the transition because "the data looks fine." It's not fine.

You're about to scale ad spend.

Scaling spend on broken measurement is scaling waste. Before you increase budget on Google Ads, Meta, or DV360, make sure the conversion data feeding those algorithms is actually accurate. Bad data in, bad optimisation out.

You suspect duplicate tracking.

Conversion numbers look suspiciously high. Engagement metrics seem inflated. You've got a gut feeling something is double-counting but can't pinpoint it. You're probably right.

You need GDPR / UK GDPR compliance confidence.

Your legal team is asking questions about data collection practices. You need to prove - technically, not just with a privacy policy - that your tracking respects consent and doesn't leak PII to third parties.

You're planning a server-side migration.

Moving to server-side tracking on a broken GA4 foundation just moves the problems to a more expensive environment. Audit first. Migrate on clean data.

How the audit runs.

trendfingers:~/ga4-audit
$ ./discover --ga4 --gtm --debugview // DAYS 1-3
GA4 property access, GTM container inspection, DebugView real-time monitoring. Mapping every event, every tag, every data flow. Building the complete picture of what's actually happening vs what you think is happening.
$ ./analyse --prioritise --reconcile // DAYS 4-7
Documenting every finding. Prioritising by business impact. Reconciling GA4 data against CRM and backend. Building the measurement plan. Writing implementation instructions for every fix.
$ ./deliver --report --walkthrough // DAYS 8-10
Full audit report delivered. Live walkthrough of every finding. Prioritised fix list with root causes and implementation steps. Measurement plan handover. No ambiguity - you know exactly what's broken and how to fix it.
$ ./implement --fix --validate --monitor // POST-AUDIT (OPTIONAL)
Direct implementation of fixes in GTM and GA4. DebugView validation for every change. 2-week post-implementation monitoring to confirm data accuracy. Optional - you can hand the report to your own team if you prefer.
✓ audit complete - data integrity verified

Stop making decisions on data you haven't verified.

A GA4 audit takes days, not months. The output is specific, actionable, and immediately implementable. If your analytics are clean, we'll confirm it. If they're not - and they usually aren't - you'll know exactly what to fix and in what order.

Request a GA4 Audit →