Click-through rate (CTR)
Also known as: CTR, click rate, clickthrough rate
Click-through rate (CTR) is the percentage of ad or search result impressions that turn into clicks, calculated as clicks divided by impressions.
CTR = clicks / impressions × 100%CTR measures how often people who saw an ad or a search snippet decided to click it. It judges the match between message and audience, not the business result. A click is a visit, and the conversion rate on the landing page decides whether that visit is worth anything.
Example
A B2B payroll platform runs two search ads on the same keyword group for a month.
Ad A: impressions 40,000; clicks 1,200. CTR = 1,200 / 40,000 × 100% = 3%. Ad B: impressions 40,000; clicks 2,000. CTR = 2,000 / 40,000 × 100% = 5%.
Ad B wins on CTR. It promises “free payroll for 3 months”, and its landing page converts to a demo request at 2%. Ad A states the price, and its visitors request a demo at 6%. Demos: 40 for B, 72 for A. The ad with the lower CTR brought nearly twice the pipeline. The numbers are illustrative.
How to use it
Use CTR to compare creatives, headlines and audiences inside one channel and placement. It also drives cost: CPC equals CPM divided by (1,000 × CTR), so a higher CTR at the same CPM makes each click cheaper. Google Ads lists expected CTR as one of the three components of Quality Score.
Always read CTR together with the next step in the funnel. Promote a creative only when it improves cost per lead or cost per customer, not CTR alone.
Common mistakes
- Comparing CTR between search and display, or between a brand and a generic keyword. The baseline differs by an order of magnitude.
- Rewarding clickbait headlines that raise CTR and lower lead quality.
- Counting accidental mobile taps and bot clicks as interest.
- Judging CTR on a few hundred impressions, where one or two clicks swing the rate.