Audience measurement
Audience measurement quantifies a website’s traffic: sessions, users, pageviews, duration, and sources. It relies on analytics tools (GA4, Matomo, Plausible) that collect data via a JavaScript tag or a server-side pixel.
In practice
Since GDPR and iOS 14, client-side measurement (JavaScript) is incomplete: ad blockers, private browsing, and consent refusal can mask 20 to 40% of real traffic. Server-side tracking and data recovery models (data blending) partially compensate for these losses. Self-hosted Matomo offers a GDPR-compliant alternative without a consent banner when correctly configured.