Customer acquisition cost, or CAC, is the average amount you spend to win one new customer. It is one of the most important numbers in any startup or subscription business, because a CAC that runs higher than the value a customer brings will quietly drain your runway. This calculator adds your total sales and marketing spend for a period, then divides by the number of new customers gained in that same period to give a clean cost per customer. Include ad spend, salaries, tools and agency fees for an honest figure. Founders use CAC to judge whether a channel is worth scaling, to set budgets and to compare paid against organic growth. Enter your spend and new customer count and read the result immediately, then pair it with lifetime value to see if the unit economics work. All math runs locally in your browser.
It divides your total sales and marketing spend by the number of new customers gained, giving the average cost to win one customer.
Include all sales and marketing costs for the period, such as ad spend, salaries and tools tied to acquisition.
Use a consistent window, such as a month or quarter, and match the spend to the new customers acquired in that same window.
Customer acquisition cost, or CAC, is the average amount you spend to win one new customer. It is one of the most important numbers in any startup or subscription business, because a CAC that runs higher than the value a customer brings will quietly drain your runway.
Yes. Customer Acquisition Cost Calculator is completely free, with no sign-up and no usage limits.
Yes. Customer Acquisition Cost Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Customer Acquisition Cost Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.