CAC Calculator

Customer Acquisition Cost, or CAC, tells you how much it costs to win a new customer, and this calculator works it out from your spend and your results. CAC is one of the most important numbers in SaaS unit economics: it is the total sales and marketing cost of acquiring customers over a period, divided by the number of new customers that spending brought in. It answers a fundamental question, what does growth actually cost, and it sits at the heart of every other efficiency metric, from the LTV-to-CAC ratio to the CAC payback period. A business that acquires customers cheaply can grow profitably and reinvest; one whose CAC is too high relative to the value each customer brings is buying growth it cannot sustain. This calculator makes the figure clear. You enter your total sales and marketing spend for the period and the number of new customers you acquired in that period, and the calculator returns your CAC, with your spend and customer count shown for reference. The results update as you type. Use it to track acquisition efficiency, to compare channels, to feed your unit-economics analysis, or to set acquisition budgets. A few good practices make CAC meaningful: include the full cost of acquisition, salaries and commissions for sales and marketing staff, advertising, tools and overheads, not just ad spend, which gives a fully loaded CAC; match the spend period to when the customers were won, allowing for any sales-cycle lag; and compare CAC against customer lifetime value, since CAC on its own is only half the story. The healthiest businesses keep CAC well below the value each customer generates, recovering it quickly and earning a strong multiple over the customer's lifetime.

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CAC = total sales & marketing spend / new customers acquired. Include fully loaded costs (salaries, ads, tools), not just ad spend. Compare against lifetime value.