Google's CMP vs a paid CMP (Sourcepoint/Didomi): the consent-rate game

Google's CMP vs a paid CMP (Sourcepoint/Didomi): the consent-rate game

What it does — both collect GDPR/TCF consent. Consent rate directly gates how many bidders can target a user, so the CMP is a revenue lever, not just compliance.

Setup effort (1-5) — Google's built-in: 1. Paid CMP: 3 (integration + A/B on banner copy/layout).

RPM lift seen — A well-tuned paid CMP lifts consent rate from ~55% to ~75%, which can mean +10-18% EU RPM because more demand qualifies. Google's CMP works but its default layout under-converts.

Pros / Cons —
Paid CMP: optimize the banner to raise consent and thus addressable RPM, granular TCF control, but a monthly fee.
Google CMP: free, fast, but you can't A/B the wall and consent rates trail.

Verdict — On heavy EU traffic, a paid CMP pays for itself purely via consent uplift. Below ~30% EU traffic, stay on Google's free CMP, the fee won't clear.

Lift: ★★★☆☆ — Risk: ★★☆☆☆
Best for: EU-heavy sites. Skip if you're mostly US/CA traffic.