The three ways to pay for an ad
You pay each time someone clicks your ad. If a thousand people saw it and nobody clicked, you pay nothing. Use it for: Google Search Ads, campaigns aimed at driving traffic to your site or landing page.
You pay for every thousand times the ad is shown, regardless of clicks. Use it for: brand awareness campaigns on Meta Ads, where the goal is to be seen, not necessarily clicked.
You pay only when the desired action happens: a form filled out, a call, a purchase. Use it for: mature campaigns with enough history for the algorithm to optimize for conversion.
Which model makes more sense for your business
In practice, most campaigns start on CPC and, once there's enough data, shift to CPA-based optimization. CPM is more common at the top of the funnel for branding campaigns.
Frequently asked questions
Does a low CPC mean a good campaign?
Not necessarily. A low CPC can mean the ad is cheap because it's reaching a low-quality audience, people who click but never convert. What matters is cost per lead or per customer, not cost per click in isolation.
Does Google Ads use CPC or CPM?
Google Ads mainly uses CPC on search campaigns, you pay per click. On Display and YouTube campaigns, CPM is more common. In Performance Max campaigns, the algorithm decides automatically which model to use.
Can I set a maximum CPC to protect my budget?
Yes. In Google Ads you can set a maximum CPC per ad group or keyword. This protects your budget in competitive auctions. Experienced agencies adjust these caps based on each keyword's conversion history.