Click-through rate is the percentage of ad impressions that produce a click: (clicks ÷ impressions) × 100. It is the quickest read on whether your creative and targeting are resonating with the audience seeing them.
Why it matters for agencies
CTR is a relevance signal, not an outcome — a high CTR with a low conversion rate points to a mismatch between the ad’s promise and the landing page. Platforms also reward higher CTR with lower CPCs, so it has a direct cost effect. Benchmark it within a channel and format, never across them.
Run the numbers with the free CTR calculator.