Cost Per Click (CPC) / Effective Cost Per Click (eCPC)

The price an advertiser is charged for each click their ad receives. Calculated as:

CPC = total cost of campaign ÷ number of clicks

CPC rates reduce risk for advertisers because payment is only triggered when someone actually clicks the ad — not simply when it's shown. That said, rates can climb significantly, reaching $20 per click or more, particularly when targeting high-demand audiences or competitive search phrases on Google.

eCPC (effective cost per click) is a derived metric that expresses what the CPC would have been if the advertiser had purchased clicks rather than impressions or conversions. It allows for apples-to-apples comparison of click efficiency across campaigns that used different buying models.