CPC vs. CPM vs. CPA
Three different ways ad platforms measure cost — per click, per thousand impressions, or per result.
What it means
CPC (cost per click) is what you pay each time someone clicks your ad. CPM (cost per thousand impressions) is what you pay for visibility, regardless of clicks. CPA (cost per acquisition) is what you pay for each actual result — a sale, a lead, a form fill.
Why it matters
Which one matters most depends on your goal. A low CPC does not mean much if those clicks never convert, and a low CPM does not mean much if nobody notices the ad. CPA is usually the number that tells you whether the campaign is actually working for your business.
ask datanephew
Which of these should I even be watching?
Ask datanephew based on your goal — if you're chasing sales or leads, it will usually point you to CPA over CPC or CPM.
My CPC went down — is that good news?
Ask datanephew to check CPA alongside it. A cheaper click that doesn't convert is not actually a win.