Why GA4 numbers and PureMetrix will not match
Different counting methods, consent behaviour and bot filtering lead to different totals. Accuracy means “good enough for the decision”, not “identical to GA4”.
What GA4 is built for
GA4 follows individual users and many events, and is tied to Google’s user tracking and estimation features. Consent Mode, hidden small numbers (thresholds) and estimated conversions can fill gaps when cookies or identifiers are missing. That is powerful for advertising—and hard to compare with a cookieless tool that counts visitors per day.
What PureMetrix is built for
- Pageviews and goals for your website
- No visitor cookies; unique visitors counted with a random value (salt) that changes daily
- Location looked up on the server (GeoIP), then the raw IP address is discarded
- Bots filtered out as data arrives
- Storage in the EU at Hetzner
Common reasons the numbers differ
| Factor | Effect |
|---|---|
| Consent / blockers | GA4 may undercount when its tags wait for consent; PureMetrix may still count if you run it without waiting for consent (the legal decision is yours) |
| How visitors are counted | GA4 links a user’s visits over time; PureMetrix does not link visitors across days |
| What counts as engagement | GA4 “engaged sessions” ≠ PureMetrix pageviews |
| Filters | Different bot lists and domain filters |
A better way to check
- Pick three pages with steady traffic and one well-known campaign.
- Compare the week-over-week trend in both tools.
- Check that your PureMetrix goals are recorded, using the troubleshooting guide.
- Stop trying to match GA4 to the decimal.
Migration guide · PureMetrix vs GA
Last updated: September 2026