How long until a customer pays you back?
Payback period, not LTV:CAC ratio, determines how fast you can grow without raising money. This calculates both properly.
Your numbers
Fully loaded monthly cost of everyone working on acquisition.
Revenue churn if you have it, customer churn otherwise.
CAC payback period
3.2 months
How long until an acquired customer has repaid what you spent to get them.
Blended CAC
$1024
All acquisition costs included.
Ad-only CAC
$706
Understates real CAC by 45%.
LTV (24-mo capped)
$7661
LTV : CAC
7.5:1
Payback at 3.2 months and a 7.5:1 ratio is a healthy structure — you can reinvest roughly 3.7 times a year without external capital.
LTV is capped at a 24-month horizon deliberately. Modelling a theoretical lifetime justifies acquisition spend you may not survive long enough to recover.
Calculated in your browser — nothing is sent anywhere, and nothing is stored.
The maths, so it isn't a black box.
It uses blended CAC, not ad-only CAC
Salaries, tools, and agency fees are included, because they're real costs of acquiring customers. Excluding them — the most common error — understates real CAC by 30–50%.
Payback uses contribution, not revenue
Monthly revenue per customer multiplied by gross margin. Using revenue would overstate how fast you recover, sometimes dramatically.
LTV is capped at 24 months
Deliberately. Lifespan derived from churn can project years out, and a five-year LTV justifies acquisition spend you may not survive long enough to recover.
It shows the gap between the two CACs
Seeing ad-only CAC beside blended CAC is usually the moment teams realize how much of their acquisition cost sits outside the ad account.
Questions about this calculation
Under 12 months for B2B SaaS and under 3 months for DTC are common rules of thumb. What actually matters is whether it's short enough for your capital position — a venture-backed company can tolerate longer payback than a bootstrapped one at identical unit economics.
Terms used here
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