One way to determine how successful an online advertising campaign has been is by looking at its Click Through Rate or CTR.

CTR is a measurement of the amount of times your ads have been clicked on. To calculate a single ad’s click through rate, you must divide the number of clicks by the amount of impressions — the amount of times an ad has been displayed on a webpage — the ad has received.

Example: You are running an advertisement that has been clicked on 50 times and has 4,000 impressions. To calculate the CTR, you divide 50 by 4,000 to get .0125. (Calculation: 50/4,000 = .0125)

You will want to express your CTR as a percentage, so you will multiply the .125 by 100, revealing that your ad has had a 1.25% click through rate. (Calculation .0125×100 = 1.25%)

The industry average CTR is about .08%, so having a 1.25% CTR means your advertising campaign is doing very well.