CTR is clicks divided by impressions — the share of people who saw an ad and clicked it. It measures whether the creative and audience match, not whether the campaign makes money.
Definition
CTR = clicks ÷ impressions. It's the fastest-reading signal of creative resonance and a component of platform quality systems, which reward engaging ads with cheaper delivery. But CTR is a mid-funnel proxy: clickbait maximizes it while destroying conversion rate, and some high-intent formats convert well at modest CTRs.
Why it matters
CTR's job is diagnosis, not destination. Falling CTR on a stable audience is the classic early symptom of creative fatigue — often visible days before CPA damage shows up. Read it as a leading indicator, never as the goal.
In agentic execution
Adlyse's agents track CTR decay curves as part of creative-rotation logic — proposing refreshes or pauses before fatigue turns into expensive conversions, with each change human-approved.
Related terms
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