Do ad blockers break my analytics?

Partially, yes — ad blockers and browser privacy features block a meaningful slice of client-side tracking scripts, so a chunk of your real visitors never appear in tools like GA4 at all.

The loss isn't evenly distributed either: technical audiences and certain browsers block far more aggressively, which quietly skews the data you do get.

You can't make everyone measurable, but first-party, server-side collection under your own domain recovers much of the gap — the events leave from your infrastructure rather than a third-party script the blocker recognizes.