How do GDPR compliance and consent flows affect analytics data?

Short answer: GDPR compliance and consent flows reduce the data collected when users decline; so your analytics data does not fully reflect reality, and the gap must be compensated with the right method.

Impact and the right approach

• Data gap: declining users are not measured, so conversions look understated
• Consent mode: govern how tags behave based on consent state
• Modeling: statistically estimate the effect of non-consented traffic
• Server-side and first-party: increase the robustness of measurement

The goal is not to bypass the law but to minimize loss within compliance and to read the report knowing this gap. The consent flow is itself a UX decision and affects conversion. Consent state is tied to the GA4 setup and the gap is reported transparently; instead of an invented exact figure, data is presented with its known limit.