What Is CAC (Customer Acquisition Cost)?
CAC (Customer Acquisition Cost) is the total amount spent on marketing and sales to win one new customer, calculated as all acquisition spend in a period divided by the number of new customers gained in that same period.
The arithmetic never changes: spend, divided by customers won. What changes by product is the thing you count on the other side of the division. A store counts paying orders, so its CAC is cost per buyer. An online course counts enrolments, so its CAC is cost per enrolment. A mobile app counts paid installs or first subscriptions, so its CAC is cost per acquired user. A software product counts paying accounts. Same formula, different unit. The most common error is leaving costs out of the top of the fraction. Ad spend is obvious, but agency fees, creative production, platform fees, and the salary of whoever runs the campaigns all belong in the numerator too. Exclude them and an unprofitable channel can look fine on paper while it quietly loses money. A CAC number on its own means nothing. It only reads as good or bad next to what a customer is worth and against your margin, not against some industry average. A cost per buyer that is fine for a high-margin course can sink a thin-margin store.
Why it matters
Most of what pushes CAC up is spend on the wrong people. Infinall works on that part directly. The Research Agent identifies specific buyer personas so ads reach likely customers instead of everyone, the Strategy Agent splits budget across funnel stages including retargeting, and the Script Agent writes copy aimed at real pain points rather than generic benefits. The aim is fewer wasted impressions and a lower cost per customer, though your actual CAC still depends on your product, price, and margin.
Related terms
Frequently asked questions
What counts as a good CAC?+
There is no universal number. A good CAC is one that sits comfortably below what a customer is worth to you over their lifetime, with room for your margin. A cost per enrolment that works for a course may be far too high for a low-margin store, so judge it against your own economics, not a benchmark.
What should I include in the CAC calculation?+
Every cost tied to winning customers in the period: ad spend, agency fees, creative production, platform fees, and the pay of anyone running the campaigns. Many owners also track paid CAC (ad spend only) and blended CAC (all marketing spend) separately to see which channels actually perform.