CTR is computed as clicks / impressions on paid media (Meta, Google, TikTok) or clicks / sends on owned messaging (email, SMS) where there is no impression event, only a delivered message. The two denominators are not interchangeable: a Meta feed CTR and a Klaviyo email CTR measure different events on different surfaces, and reading them as a single rate across a dashboard is a common operator error.
CTR is a creative and targeting diagnostic, not a business outcome. It tells you whether the unit earned the click given exposure; it says nothing about whether the click converted, generated revenue, or reached an audience worth reaching. In paid-media funnel arithmetic — impressions × CTR × CVR — it sits between impression and on-site conversion. Earning the click is not earning the customer.
Three operator traps. Optimizing creative to CTR while CAC rises: clickbait lifts the rate but recruits weak-intent clicks that convert below baseline. Reading CTR without CVR or ROAS: the rate alone shows attention, not outcome. Cross-channel comparison: branded-search CTR on Google, prospecting CTR on Meta, and email CTR are different constructs with different denominators and different intent surfaces. The brand’s own baseline is the reference.