CAC Calculator
(Customer Acquisition Cost Tool)
Work out customer acquisition cost from spend and new customers. Switch modes to plan a budget, and add lifetime value for LTV:CAC and payback.
Step 1 — Calculation Goal
What would you like to calculate?
Step 2 — Core Metrics
All ad spend plus sales/marketing salaries, tools, and overhead for the period
Total new paying customers gained in the same period
CAC Result
💡 Formula Guide
This CAC calculator works out customer acquisition cost, the average amount a business spends to win one new paying customer. Enter sales and marketing spend and the number of new customers to get the CAC. You can also start from a target CAC to plan a budget or estimate how many customers a budget will bring. Add lifetime value and monthly revenue per customer for the LTV:CAC ratio and the payback period.
How to Calculate CAC
CAC is total sales and marketing spend divided by the new customers won in the same period.
A business that spent $12,000 in a month and gained 60 customers has a CAC of $12,000 ÷ 60 = $200.
| To find | Formula | Example |
|---|---|---|
| CAC | Spend ÷ New Customers | $12,000 ÷ 60 = $200 |
| Budget | Target CAC × Customers | $200 × 50 = $10,000 |
| Customers | Budget ÷ Target CAC | $10,000 ÷ $200 = 50 |
What to Include in the Spend
The result is only as honest as the spend figure. A full CAC counts:
- Advertising on every channel
- Pay and commission for sales and marketing staff
- Agencies, freelancers and contractors
- Sales and marketing software
- Content, events and sponsorships
Match the timing as well. If a sale takes three months to close, this month's customers were won by spending from three months ago. Businesses with long sales cycles often compare this quarter's customers with last quarter's spend.
Blended CAC and Paid CAC
Not every customer comes from paid marketing. Dividing all spend by all customers gives blended CAC, which can hide how expensive the paid channels are.
| Measure | Spend | Customers counted | CAC |
|---|---|---|---|
| Blended CAC | $12,000 | 60 (all new customers) | $200 |
| Paid CAC | $12,000 | 40 (from paid channels) | $300 |
Blended CAC describes the business as a whole. Paid CAC tells you what the next customer bought through advertising will cost. For a single campaign, the CPA Calculator gives cost per acquisition.
LTV:CAC Ratio and Payback Period
A CAC means little alone. A $200 CAC is cheap for a customer worth $2,000 and ruinous for one worth $150. Two figures put it in context.
With a lifetime value of $900 and a CAC of $200 the ratio is 4.5:1. If that customer pays $75 a month, the CAC is earned back in 200 ÷ 75 = 2.7 months.
The usual guideline comes from David Skok's SaaS Metrics 2.0, which says the best SaaS businesses have a lifetime value more than 3 times CAC, sometimes as high as 7 or 8, and that many of them recover CAC in 5 to 7 months. It was written about software subscriptions, so treat it as a reference point for other kinds of business. The calculator's payback uses revenue; enter monthly gross profit per customer for a stricter figure. The LTV:CAC Ratio Calculator can estimate lifetime value if you do not have it.
How to Use the CAC Calculator
- Choose what to solve for: Pick customer acquisition cost, the budget needed for a customer goal, or the customers a budget will bring.
- Enter the two known values: Type in two of sales and marketing spend, new customers and target CAC. The third is calculated as you type.
- Add lifetime value: Optional. Enter customer lifetime value to see the LTV:CAC ratio.
- Add monthly revenue per customer: Optional. Enter the average monthly revenue from one customer to see how many months it takes to earn the CAC back.
Frequently Asked Questions
How do I calculate customer acquisition cost?
Divide everything spent on sales and marketing in a period by the number of new customers won in that period. A business that spent $12,000 and gained 60 customers has a CAC of $12,000 ÷ 60 = $200.
What costs should be included in CAC?
Advertising, the pay of sales and marketing staff, agency and freelancer fees, sales and marketing software, and content and event costs. Leaving out salaries gives a lower figure that is closer to cost per acquisition for ads than to the full cost of winning a customer.
What is the difference between CAC and CPA?
CPA is the cost of one action from one campaign, and the action may be a lead or a sign-up, not a paying customer. CAC is the full cost of winning a paying customer across all sales and marketing.
What is a good CAC?
One that is small compared with what a customer is worth. David Skok's SaaS Metrics 2.0, the usual source for this rule, says the best SaaS businesses have a lifetime value more than 3 times CAC, and that many of the best recover their CAC in 5 to 7 months.
How do I calculate the CAC payback period?
Divide CAC by the monthly revenue from one customer. A $200 CAC and $75 a month gives 200 ÷ 75 = 2.7 months. For a stricter figure, use monthly gross profit: at an 80% gross margin the customer brings $60 a month, and payback is 3.3 months.
What is blended CAC?
Blended CAC divides total spend by all new customers, including those who arrived without advertising. Paid CAC divides the spend by only the customers who came from paid channels, so it is higher. Use paid CAC to judge whether more ad spend will pay.
The 3:1 and payback guidelines were checked against David Skok's SaaS Metrics 2.0 in October 2026.