Marketing & ecommerce

Customer Acquisition Cost (CAC) Calculator

Combine marketing and sales expenses to measure the cost of a new customer.

Free, no sign-upRuns in your browserReviewed October 2026Formula & methodology
US dollars
US dollars
customers

Results update as you type. Your numbers stay in this browser.

Customer acquisition costExample$80.00
Total acquisition expenses
$8,000
Average per nonzero expense group
$4,000

Understand the result

What is Customer Acquisition Cost (CAC)?

Customer acquisition cost (CAC) is the average sales and marketing spend needed to win one new customer. Add the marketing and sales expenses for a period and divide by the new customers acquired in that period: $8,000 spent to win 100 customers is an $80 CAC.

Blended CAC(Marketing + Sales expenses) ÷ New customers
Paid CACPaid media spend ÷ Customers from paid channels
Payback monthsCAC ÷ Monthly contribution per customer

Example: a B2B software startup’s month

  1. Ads, content and tools: $5,000
  2. Sales commissions and the sales rep’s share of salary: $3,000
  3. New paying customers: 100
  4. CAC: $8,000 ÷ 100 = $80

If each customer contributes $30 a month after service costs, the $80 is recovered in about 2.7 months.

What to include

  • Ad spend, agency and freelancer fees, marketing tools and content production.
  • Sales salaries and commissions attributable to winning new customers.
  • Leave out costs of serving existing customers, such as support and account management.

Common mistakes

  • Counting only ad spend. Paid CAC is useful, but blended CAC with salaries is what the business actually pays.
  • Ignoring sales-cycle lag. If deals take three months to close, compare this month’s customers with the spend from earlier months.
Common questions

Customer Acquisition Cost (CAC) FAQ

What is a good CAC?

One that your customers repay quickly and many times over. Compare CAC with profit-based lifetime value and with the payback period your cash allows.

Should CAC include salaries?

For blended CAC, yes: include the share of sales and marketing salaries spent on acquiring new customers. Report paid-channel CAC separately if you also want it.

How do I lower CAC?

Improve conversion rates, focus spend on the channels with the best cost per customer, and grow referrals and organic search, which add customers without proportional spend.

Guides for this calculation

Build context around the numbers with worked examples from our guides.

CAC Payback Period: Calculate Months to Recover Acquisition Cost →