Analytics Reference
Conversion Tracking Reference
Conversion tracking is now a portfolio of partly redundant methods rather than one tag. Browser restrictions mean client side alone under reports, and every platform has its own answer. This is the map I use when auditing a measurement stack.
| Method | How it works | Strength | Weakness |
|---|---|---|---|
| Client side tag | JavaScript fires in the browser | Simple to deploy | Blocked by ad blockers and ITP |
| Server side tagging | Events sent from your own server | More durable, first party context | Infrastructure and maintenance cost |
| Conversions API | Server to platform event feed | Recovers lost browser events | Needs deduplication with the pixel |
| Enhanced conversions | Hashed first party data sent with the conversion | Improves match rate | Requires consent and correct hashing |
| Offline conversion import | CRM outcomes uploaded back to the platform | Ties spend to real revenue | Needs a click identifier stored in the CRM |
| Platform | Click identifier | Where to store it |
|---|---|---|
| Google Ads | gclid, or wbraid and gbraid | Hidden form field, then CRM record |
| Microsoft Ads | msclkid | Hidden form field, then CRM record |
| Meta | fbclid, plus fbp and fbc cookies | Captured for Conversions API events |
| li_fat_id | Used with the conversions API |
Notes
Capture the click identifier into a hidden form field on every lead form and write it to the CRM record. This is a small piece of work that unlocks offline conversion import later, and without it you can never connect closed revenue back to the campaign that produced it. Doing it after the fact is impossible for historical leads.
When you run both a browser pixel and a server side conversions feed, deduplicate with a shared event identifier or you will double count. Every major platform supports an event ID for exactly this, and the most common server side implementation failure I see is skipping it and then celebrating a fake lift.
Do not expect platform reported conversions to match GA4 or your CRM. They use different attribution models, different lookback windows and different definitions of a conversion. Pick one system as the source of truth for business decisions, usually the CRM, and use platform numbers for in platform optimisation only.
Browser privacy behaviour, consent requirements and platform APIs change frequently, and version numbers and parameter names change with them. Verify against the current Google Ads, GA4 and Meta developer documentation before building an implementation.
Frequently asked questions
Do I still need the browser pixel if I have a server side feed?
Yes in most cases. Running both with proper deduplication gives the best coverage, because each captures events the other misses.
Why does Google Ads report more conversions than GA4?
Google Ads uses ad click based attribution with its own lookback window and counts conversions on the click date, while GA4 attributes across all channels on the conversion date. Different questions, different numbers, both can be correct.
What is the first thing to fix in a broken setup?
Define the conversions that matter and count each one once. Most broken accounts are optimising toward duplicated or trivial events, which is worse than under measuring.
Official sources
Platforms change specifications without notice. Check the primary documentation before a launch that depends on an exact value.
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