The percentage of individuals viewing a web page who click on a specific advertisement that appears on the page. Click-through rate measures how successful an ad has been in capturing users' interest. The higher the click-through rate, the more successful the ad has been in generating interest. A high click-through rate can help a website owner support the site through advertising dollars. Because Internet users have become desensitized to ads on web pages, a typical click-through rate is only about two to three users per 1,000.