Metrics & KPIs
What is CPA (cost per acquisition)?
CPA (cost per acquisition, also cost per action) is what you pay for one desired action — usually a purchase or a lead: ad spend divided by the number of conversions. It is one of the most important profitability metrics in Meta ads.
Formula
CPA = ad spend ÷ conversions
Example
Spend $300 and get 20 purchases → CPA = 300 ÷ 20 = $15. If your product margin is $25 you're profitable; at a $12 margin you're losing money on every sale and need to cut CPA or raise order value.
Why it matters
As long as your CPA stays below the margin on an order, the campaign makes money — which makes CPA the cleanest go/no-go signal for scaling or pausing an ad set. Set your maximum acceptable CPA from your margin, not from a feeling, and let automated rules police it for you.
How to use and improve it
Lower CPA by improving the landing-page conversion rate, tightening creative-to-offer match, and pausing the ad sets whose CPA runs above your ceiling. Because CPA = traffic cost ÷ conversion rate, fixing the page often beats fiddling with targeting.
Frequently asked questions
What's the difference between CPA and CPC?
CPC is the cost of a click; CPA is the cost of a completed action such as a purchase or lead. You can have a low CPC and still a high CPA if the clicks don't convert.
What is a good CPA on Facebook?
A good CPA is any figure comfortably below your profit per conversion. The right number therefore depends entirely on your margins, not on an industry average.
What's the difference between CPA and CPL?
CPL (cost per lead) is a specific type of CPA where the action is capturing a contact. CPA is the broader term covering any target action, most often a sale.
Related
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