Cost per acquisition (CPA)
CPA is what you pay, on average, for one conversion: cost divided by conversions. It is the clearest single number for what a lead or sale costs you.
In the platformBasics
Cost / conv.
CPA is what you pay, on average, for one conversion: cost divided by conversions. It is the clearest single number for what a lead or sale costs you.
If a conversion is a lead, a booking or a sale, CPA is what that result costs you in ad spend. It is only as reliable as your tracking: if page views or duplicate events count as conversions, CPA looks better than reality. CPA works best when conversions have similar values; when order values vary a lot, ROAS is usually the better lens.
Where you'll see it
In Google Ads the column is "Cost / conv." in the Campaigns, Ad groups and Keywords tables (add it under Columns > Conversions if it is missing). It uses the actions in the "Conversions" column, which are your primary conversion actions. Meta Ads Manager shows "Cost per result" for the campaign's optimization event; TikTok Ads Manager shows "Cost per conversion".
Worked exampleA lead campaign: $3,000, 60 leads
- CPA = $3,000 ÷ 60 = $50 per lead
- If 1 in 5 leads becomes a customer: $50 × 5 = $250 per customer
- If a customer is worth $400 in gross profit: $400 − $250 = $150 left after ad spend
Before you trust a CPA
- Only primary, non-duplicate actions count as conversions.
- The campaigns you compare track the same conversion actions.
- Recent days may still get conversions within the conversion window.
- You know what a lead or sale is worth before setting a CPA goal.