CAC Calculator
Total sales and marketing cost over new customers gives CAC. Add monthly revenue per customer and margin to see how long each customer takes to pay back.
Blended CAC
–
All sales and marketing cost ÷ new customers
- Paid CAC
- –
- Needs paid spend and paid customers
- Marketing-only CAC
- –
- Marketing spend ÷ new customers
- Gross profit per customer
- –
- Per month
- CAC payback
- –
- Needs revenue per customer and margin
What CAC includes, and why the blended number matters
CAC is the fully loaded cost of winning one paying customer. Not the ad cost per lead, not the cost per signup: the total cost of sales and marketing divided by customers who actually paid. Salaries, agency retainers, tooling, content, events, and media all belong in the numerator. Leave them out and you get a number that looks good in a deck and falls apart in a board meeting.
Blended CAC and paid CAC answer different questions. Blended tells you what growth costs the business overall, and it's the figure that pairs with lifetime value in unit economics. Paid CAC isolates the channels where spend is a dial you can turn, and tells you whether turning it further still makes sense. When paid CAC sits well above blended, organic and referral customers are subsidising the paid programme. That's normal, but it means paid can't scale indefinitely at that price.
Payback turns a cost into a timeline. Divide CAC by the gross profit a customer generates each month and you get the months it takes to recover the acquisition cost. Gross profit, not revenue: a customer paying $400 a month at 70% margin contributes $280, so an $800 CAC takes just under three months to earn back. Payback is the metric finance uses to decide how much growth the balance sheet can afford.
Formulas
- Blended CAC
- = (Marketing spend + Sales spend) ÷ New customers
- Paid CAC
- = Paid media spend ÷ Customers from paid channels
- Marketing-only CAC
- = Marketing spend ÷ New customers
- Gross profit per customer per month
- = Monthly revenue per customer × Gross margin
- CAC payback (months)
- = Blended CAC ÷ Gross profit per customer per month
Frequently asked questions
How do you calculate customer acquisition cost?
Add up everything spent on sales and marketing in a period, then divide by the number of new customers won in that period. $200,000 of combined spend that produced 250 new customers is a CAC of $800. Include salaries, agency fees, tools, and media, not just the ad budget, or the number will flatter you and finance will recompute it.
What is the difference between blended CAC and paid CAC?
Blended CAC divides all sales and marketing cost by all new customers, including those that arrived through referrals, organic search, and word of mouth. Paid CAC divides paid media spend by the customers that media produced. Blended is the number for unit economics and board decks. Paid is the number for deciding whether a channel can take more budget. They can diverge sharply, and both are worth tracking.
What is a good CAC payback period?
It depends on gross margin, contract length, and how much cash you have. Subscription businesses often aim for payback inside 12 months, and many venture-backed companies tolerate 18 to 24 months when retention is strong. Payback longer than the typical customer lifetime means the acquisition cost is never recovered at all, whatever the CAC looks like on its own.
More free tools
Browse all free tools →- LTV Calculator Calculate customer lifetime value from revenue, margin, and churn, and check your LTV to CAC ratio.
- Marketing ROI Calculator Calculate marketing ROI and ROMI on gross margin, not just revenue, across one or several campaigns.
- Churn Rate Calculator Calculate customer and revenue churn, retention, and expected customer lifetime.
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