CAC Payback Period Calculator

Estimate how many months it takes to recover CAC via gross profit.

Prefer an explanation? Read the guide.
 
$
 
$
 
%
Tip: you can type commas (e.g., 10,000).

Example

Using the default inputs, the result is:
3.1 months
CAC
$500
ARPA per month
$200
Gross margin
80%

Formula

Payback (months) = CAC ÷ (ARPA × Gross Margin)
  • ARPA and gross margin remain stable over the payback period.

FAQ

Should payback include onboarding costs?
If onboarding costs are significant and variable per customer, include them in CAC so payback reflects full acquisition cost.

How to interpret

How to interpret payback
  • Shorter payback improves cash efficiency and reduces risk.
  • Compare payback by channel—some channels are slow but scalable.
  • Pair with churn: long payback + high churn is dangerous.