Why numbers differ from Google Analytics 4
The usual reasons Privatus and Google Analytics 4 report different numbers: consent banners, ad blockers, visitor and bounce definitions, bots and timezones.
It's normal for Privatus and GA4 to disagree, often by 10 to 50%. The main reasons, roughly in order of size:
1. Consent banners#
GA4 usually runs only after a visitor accepts cookies. Depending on your banner and audience, 30 to 70% of visitors in Europe decline or ignore it. With Consent Mode, GA4 models some of the missing data, which adds estimates on top. Privatus doesn't need consent in most setups, so it counts visitors GA4 never sees.
2. Ad and tracking blockers#
Blockers stop GA4 more often than Privatus, but some blockers stop Privatus too, so both tools can undercount. See Ad blockers.
3. Different definitions#
| Privatus | GA4 | |
|---|---|---|
| Users / visitors | Unique per day, summed over the range | Unique over the whole range, based on a cookie or signed-in user id |
| Sessions / visits | 30 min inactivity, ends at midnight UTC, no campaign-based restarts | 30 min inactivity, can span midnight |
| Bounce | 1 pageview and no event and < 10 s engaged | Not "engaged": < 10 s, no conversion, one page |
| Engagement time | Visible time only | Foreground time |
Because visitors are counted per day, weekly and monthly visitor totals are higher in Privatus than GA4's users for the same people. Compare daily numbers, or pageviews, for a fair check.
4. Bot filtering#
Both filter bots, with different lists. Privatus also filters data-center traffic and headless browsers by default, and shows how many hits it removed in the Overview's footer.
5. Timezones and date boundaries#
Check that both tools use the same timezone. See Timezones.
6. Where the script runs#
Make sure both scripts are on the same pages. Single-page apps, excluded paths, staging hostnames and Google Tag Manager triggers often differ.
A fair comparison#
Pick one day, compare pageviews for a handful of top pages, with the same timezone and hostname. Pageviews are the most comparable metric. The remaining gap is mostly consent and blockers.
To bring your GA4 history over, see Imports.