← Glossary
Influencer Marketing
CPA (Cost Per Acquisition)
The cost per completed sale, sign-up, or other conversion driven by a creator's content. The most direct way to measure influencer marketing ROI.
What it means
CPA sits closest to the bottom line: what it cost to get one paying customer, subscriber, or lead from a piece of influencer content. Divide total campaign spend by the number of tracked conversions. Because it accounts for the full funnel, from view to click to purchase, CPA compares directly to what a brand pays for a customer through any other channel, like paid search or display ads.
Examples
- •A campaign spends $3,000 and generates 60 sign-ups, a $50 CPA.
- •A brand compares influencer CPA against its Facebook ads CPA to decide where to put next quarter's budget.
- •A subscription box brand tracks CPA separately for each creator's unique promo code.
Use cases
- •Justifying influencer spend against other acquisition channels in a budget review.
- •Deciding which creators to re-book based on conversion efficiency, beyond reach alone.
- •Setting a target CPA ceiling before a campaign launches to control spend.
Why it matters
CPA decides whether influencer marketing gets treated as a real growth channel or a one-off experiment. A consistently reasonable CPA is what unlocks bigger, repeatable budgets.
Common questions
CPA tells you the cost of one conversion. ROI tells you overall profitability of the whole campaign against spend. A campaign can post a great CPA and still lose money if the product's margin is thin.