CAC Calculator: calculate cac for your business. Formula, benchmarks, and practical tips included.
Customer acquisition cost (CAC) is the total cost of acquiring a new paying customer, including all sales and marketing expenses divided by the number of new customers gained in the same period. CAC is one of the most critical SaaS and subscription business metrics — when compared against customer lifetime value (LTV), it determines whether a business model is fundamentally viable. The LTV:CAC ratio must be sufficiently high to justify the acquisition investment and sustain growth. Profit Margin Calculator is the essential companion metric to CAC for business model assessment.
CAC = Total sales and marketing costs ÷ New customers acquired
CAC payback period = CAC ÷ Monthly gross margin per customer
Worked example: Monthly sales and marketing costs: 150,000. New customers acquired: 300. CAC = 500. Monthly gross margin per customer: 80 (subscription 120 × 67% gross margin). CAC payback = 500/80 = 6.25 months. LTV at 24-month average customer life: 80 × 24 = 1,920. LTV:CAC = 1,920/500 = 3.84× — healthy unit economics.
LTV:CAC benchmarks: below 1:1 — value-destroying, the business costs more to acquire customers than they are worth; 1:1 to 2:1 — unprofitable, not sustainable at scale; 3:1 — standard benchmark for healthy SaaS unit economics; 5:1+ — highly efficient, may indicate underinvestment in growth. CAC payback period benchmarks: under 12 months — excellent; 12–18 months — good for SaaS; 18–24 months — acceptable for enterprise SaaS; over 24 months — concerning cash flow strain. CAC varies enormously by channel: organic/inbound typically 2–5× lower than outbound/paid.
CAC is a management accounting metric not defined by any accounting standard. For investor reporting, ensure CAC definitions and calculation methodologies are clearly disclosed and applied consistently. LTV projections used in fundraising materials are forward-looking statements and subject to applicable securities law. This calculator is for internal planning purposes only.