Google Ads glossary
Click-through rate, or CTR, is the share of people who click your ad out of those who see it: the number of clicks divided by the number of impressions, the times your ad was shown.
CTR = clicks ÷ impressions. 5 clicks on 100 impressions give a CTR of 5%. Each ad and each keyword has its own CTR.
A high CTR suggests people find the ad relevant. What counts as a good CTR depends on what you advertise and on the network. Expected click-through rate is also one of the three components of Quality Score.
A high CTR is not enough. A catchy headline on a search with no buying intent attracts clicks from browsers: the CTR goes up, so does the bill, and sales do not.
By contrast, a low CTR on a buying keyword often means the ad does not answer the search. Read CTR together with the keyword’s intent, never alone.
Say an ad is shown 2,000 times and clicked 60 times: its CTR is 3%. If most of those clicks come from searches like “free” or “definition”, that CTR hides a problem: the clicks are not from buyers.
Free tool: Ad preview
The ad preview shows how your ad will look on desktop and mobile, and checks that your keyword appears in a headline.
Official source: Google Ads Help: clickthrough rate (CTR)