FINBIZTOOLS
CAC Calculator
Calculate customer acquisition cost (CAC) from your sales and marketing spend and the number of new customers acquired in the same period.
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Changes the currency symbol and number format only. Amounts are not converted.
How to use the CAC Calculator
- Enter sales spend for the period.
- Enter marketing spend for the same period.
- Enter the number of new customers acquired in that period.
- Select Calculate to see total spend and the customer acquisition cost.
Use the currency selector above the inputs to change the symbol. It changes the display only and does not convert amounts.
What is CAC?
Customer acquisition cost (CAC) is the average cost of acquiring one new customer, calculated from total sales and marketing spend divided by new customers acquired over the same period.
CAC is commonly compared against customer lifetime value (LTV) to judge whether acquisition spend is proportionate to the value each customer brings — see the LTV:CAC Calculator.
How the calculation works
CAC formula
CAC = (Sales spend + Marketing spend) ÷ New customers acquired
- Sales spend and marketing spend are total costs for the period, in whatever categories you track them.
- New customers acquired is the count of new customers gained in that same period.
This uses whatever figures you enter for sales and marketing spend; it does not automatically include product, support, onboarding or overhead costs unless you add them into the spend figures yourself.
CAC calculation example
Sales spend of 20,000 and marketing spend of 30,000, acquiring 100 new customers:
| Sales spend | 20000 |
|---|---|
| Marketing spend | 30000 |
| New customers acquired | 100 |
| Total sales & marketing spend | 50000 |
|---|---|
| New customers acquired | 100 |
| Customer acquisition cost (CAC) | 500 |
Amounts are shown without a currency symbol because the arithmetic is identical in any currency; the currency selector only changes the symbol and number format.
Assumptions and limitations
Assumptions
- Sales and marketing spend and new customers acquired refer to the same period; a lag between spend and the resulting customers is not modeled.
- This is a blended CAC across all acquisition channels; it does not separate cost by channel or campaign.
Limitations and why results can differ
- It does not include indirect costs (such as a portion of general overhead) unless you fold them into the spend figures yourself.
- A single period's CAC can be noisy, especially with a small number of new customers; many businesses track a rolling average instead.
Frequently asked questions
How is CAC calculated?
CAC is total sales and marketing spend for a period divided by the number of new customers acquired in that same period.
Does CAC include product or support costs?
Not unless you include them in the spend figures. This calculator only totals whatever sales and marketing spend you enter.
Why do sales and marketing spend need to be from the same period as new customers?
Mixing periods (for example, this month's spend against last month's new customers) can distort CAC, especially with sales cycles that span multiple months.
What do I do with my CAC figure next?
A common next step is comparing it with customer lifetime value using the LTV:CAC Calculator.
Methodology
Sales spend and marketing spend are each validated from 0 to 1,000,000,000,000 and summed. New customers acquired is validated as greater than zero (0.01 to 1,000,000,000, so a division by exactly zero is rejected).
CAC = total spend ÷ new customers, computed directly with no intermediate rounding before display rounding. The calculation runs in your browser and inputs are not sent to a server.
Last reviewed:
Disclaimer
Results are calculated estimates based on the figures you enter. They are not accounting, pricing, tax or legal advice. Verify important business and pricing decisions with your own records and a qualified professional. Read the full Disclaimer.
Explore this topic
This tool is part of SaaS and Startup Metrics.
A common order: measure recurring revenue and churn, compare customer value with acquisition cost, then check runway.