In this guide
- GA4 does not log or store IP addresses in the way Universal Analytics did, and the old anonymize-IP setting no longer exists.
- Your tagging server and other tags can still see the IP. The Anonymizer power-up zeroes the last part of it (Partial) or removes it (Full) before it reaches your container.
- The cost: tags that use the IP, such as GA4's city and Meta's matching, get less to work with.
IP addresses are personal data in the EU, so many teams ask whether they are protected when they use analytics. This page separates what GA4 itself does from what happens in a server container, and shows where the Anonymizer fits. This is general information, not legal advice. See also GDPR and server-side tracking and personally identifiable information.
What GA4 does
Universal Analytics had an "anonymize IP" setting that cut the last part of the address. In GA4, Google says it does not log or store IP addresses, and it uses the IP to derive approximate location and then discards it. The old setting is therefore not needed and not available. Whether this meets your legal needs is for your advisor to decide.
Runs on your domain, anywhere
Your tracking runs on your own domain, so a visit from any country is handled the same way.
What your server sees
A browser request to your tagging subdomain carries the visitor's IP address, like any web request. The server container can read it and pass it to tags. Meta, for example, uses the IP and user agent in its Conversions API matching. If you do not want the full address to reach your container at all, you need to hide it before the container. That is what the Anonymizer is for.
The two levels
| Level | What happens | Effect |
|---|---|---|
| Partial | The last part of the IPv4 address is set to zero | Rough location still possible; weaker matching |
| Full | No address is sent | No location from the IP; tags that need it get nothing |
The Anonymizer is on every Open Tracked plan, including Free. You choose the level and press Save, and the rule is applied to your tagging server within a few seconds. You test it in GTM Preview: the visitor address of an incoming request ends in .0 for Partial, or is empty for Full.
Check your tracking in one pass
This is an example. Run the check on your own site to see where yours stands.
What you lose
- GA4 city and region may be less precise or missing.
- Meta and other ad platforms use the IP for matching. Without it, match quality can fall.
- Fraud and bot checks that rely on the IP have less to work with.
Visitor Location with anonymized IPs
The Visitor Location power-up adds country, region, city and postcode from the headers your CDN sends. Those are derived at the edge, before the Anonymizer, so you can keep location data while hiding the address from the container. Check what your CDN provides.
When to use it
- you want to reduce exposure but keep rough location
- your legal advisor accepts truncated addresses
- you do not need the IP for any tag
- your policy says addresses must never reach your server logs
Test
- Turn on the Anonymizer and choose a level.
- Press Test this power-up.
- Open GTM Preview and send a request.
- Read the visitor address of the request: it ends in
.0(Partial) or is empty (Full). - Check match quality in Meta over the next week.
Questions to settle with your advisor
Before you choose a level, ask three questions. Does your organisation treat a truncated IP address as personal data? Do you rely on IP-based matching for ad performance, and how much? Do your server logs keep addresses, and for how long? The answers decide whether Partial is enough or Full is needed, and whether the cost to matching is acceptable. Write down the decision and the reason, and review it when your tools or the rules change.
Remember that the Anonymizer affects what reaches your tagging container. Your CDN, your web server and other services may still see the full address. If your goal is that no system stores IP addresses, look at the whole chain, not only the container.
Watch events arrive, live
A sample feed. In Open Tracked you see the same stream for your own store.
Frequently asked questions
Does GA4 anonymize IP addresses?
Google says GA4 does not log or store IP addresses, and the old anonymize-IP setting no longer exists.
Can my tagging server see the IP?
Yes, unless you hide it before it reaches the container. The Anonymizer power-up does that.
What does the Anonymizer do?
Partial sets the last part of the address to zero. Full sends no address.
Will anonymizing hurt tracking?
It can reduce location precision and ad-matching quality.
Is the Anonymizer free?
It is on every Open Tracked plan.
Do I need spreadsheets to read my results?
No. Once tracking is live, the Open Tracked analytics shows spend, revenue, ROAS and profit, and you can ask Ari, the built-in AI assistant, questions about your own numbers in plain words. Ari's allowance depends on your analytics plan.
Is Open Tracked different from Open Track or Open Space Track?
No. Open Tracked is the official name of our server-side tracking platform, and the website is opentracked.io. Many people search for it as Open Track, OpenTrack or Open Space Track. All of them lead to the same product: server-side Google Tag Manager hosting, first-party analytics and a CRM pipeline.
Fix your tracking at the source
Open Tracked hosts your server-side Tag Manager, keeps first-party cookies alive and shows what each ad is really worth.
The Open Tracked team
We build Open Tracked: server-side tracking hosting, analytics and the tools around them, for stores that spend on ads. Questions about this guide, or an idea for the next one?
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