What is CPA (Cost Per Action)?

CPA (Cost Per Action) is both a payment model and the metric “cost per target action”: lead, signup, install, purchase, deposit. In affiliate marketing, advertisers or networks pay affiliates a fixed or dynamic payout per approved action.

CPA as a buying model

In ad accounts, target CPA bidding optimizes toward a set conversion price. The buyer sets target CPA; the algorithm adjusts bids. Real CPA in the tracker = ad spend ÷ conversions.

CPA vs CPL, CPI, CPS

• CPL — CPA subset (lead).
• CPI — app install.
• CPS — sale, often % of order.

In arbitrage

Funnels profit when effective CPA (cost/conversions) < payout after approval. Offer caps limit scale. Holds delay payouts—cash ROI differs from accounting ROI.

Metric limits

“Conversion” in ad account vs network may differ (view-through, status rules). CPA without CR and volume is incomplete—use ROI and EPC.

See also: CPL, CPI, payout, affiliate network.