CAC calculator
CAC is total sales and marketing cost divided by new customers won. Nine thousand of media plus a thousand of salaries across 100 customers is a fully loaded CAC of 100. Against a media-only figure of 90.
How to calculate CAC
The period mismatch is the subtle error. Spend in January often wins customers in March, so dividing one month spend by the same month customers is noisy at best and wrong at worst for anything with a long consideration cycle. Using a rolling three-month window smooths it. The other judgement is which customers count: including those who arrived organically makes CAC look better but makes it useless for deciding how much more to spend, since organic arrivals do not scale with budget.
Questions
Total sales and marketing cost divided by the number of new customers won in the same period.
For a true figure, yes. Media-only CAC is useful for channel comparison but understates what a customer really costs.
Include them for a blended CAC, exclude them for a paid CAC. The paid figure is the one that tells you what more budget will cost.
There is no absolute answer; it only means something against lifetime value. Aim for LTV at least three times CAC.
Usually a timing mismatch between spend and conversion. A rolling three-month window smooths it.