CAC calculator
Customer acquisition cost, blended and paid, with LTV, the LTV:CAC ratio and your payback period. No signup, no email — the numbers never leave your browser.
Blended CAC hides which channel produced which customer — it is one number for every source you paid for. The gap between blended and paid CAC here is $125 per customer, and neither figure tells you whether it was search, social or an AI assistant that earned them.
The formulas
Shown, so you can check them.
Nothing here is proprietary and none of it is a benchmark — it is arithmetic on the numbers you typed.
Blended CAC
(Ad spend + sales and marketing cost) ÷ new customers. Everything you spent, over everyone you won.
LTV
Average order value × lifetime in months × gross margin. Gross profit, not revenue — revenue-based LTV flatters every ratio it touches.
CAC payback
CAC ÷ monthly gross profit per customer. Months until the customer has repaid what they cost.
FAQ
The questions that come up every time.
How is CAC calculated?
Total sales and marketing cost divided by new customers won in the same period. Blended CAC includes salaries, tools and agency fees; paid CAC counts ad spend alone. Both are useful and they answer different questions.
What is a good LTV:CAC ratio?
3:1 is the figure most SaaS investors quote, and it is a rule of thumb rather than a law — it assumes a gross margin and a churn rate that may not be yours. The calculator shows the ratio; whether it is healthy depends on your payback period and how much cash you can carry.
What is CAC payback?
How many months of gross profit it takes to repay what you spent acquiring a customer. It matters more than the ratio for anyone not raising: a 4:1 LTV:CAC with a 20-month payback can still run you out of cash.
Why is blended CAC misleading?
It is one number for every source you paid for, so it cannot tell you that search customers cost a third of what social ones do. Splitting CAC by channel needs the conversions attributed to their source first — which is the gap between this calculator and knowing what to cut.
A calculator cannot tell you which channel produced them.
This works out the cost. Splitting it by the source that produced each customer is the part that changes where the budget goes — one script tag, 28 days free.