What Click-Through Rate is: the rate at which your audience “clicks through” to your target, calculated by taking the number of clicks on your link, and dividing that by the total number of impressions of your link.
What Click-Through Rate is not: an educated guess; a magical number that will immediately give you the answers to life, the universe, and everything.
Why we care about Click-Through Rate: Click-through rate (CTR) is a major indicator of how well your link is targeting your audience. The higher the CTR, the better, although the actual number will depend greatly on what you are testing. A test of your click-through rate will require knowledge of your page, ad, or keyword impressions during a time period, and how many click-throughs happened in that same time period.
This post is part of an ongoing Clickipedia series, defining all the terms you need to know for conversion rate optimization. Keep checking back each week to learn more, and don’t forget to check out the whole series.