Customer Acquisition Cost (CAC) Calculator

Calculate your customer acquisition cost (CAC), LTV:CAC ratio, and payback period. See whether your growth economics are sustainable and benchmark against SaaS and e-commerce norms.

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. Page Speed Calculator is the essential companion metric to CAC for business model assessment.

Sum all sales and marketing costs for the period: ad spend, sales team salaries, commissions, marketing tools, agency fees, trade shows, content production.
Enter the number of new paying customers acquired in the same period.
CAC = Total sales and marketing costs ÷ New customers acquired.
Calculate blended CAC (all channels) and by-channel CAC to identify most efficient acquisition sources.
Compare CAC against LTV — target LTV:CAC of 3:1 or higher for sustainable unit economics.

CAC formula

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.

Interpreting CAC and LTV:CAC

SaaS unit economics benchmarks

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.

Business tips and best practices

Allocate all fully-loaded costs — include a proportional share of marketing team salaries, tools, and overhead, not just direct ad spend.
Calculate CAC payback in months separately from LTV:CAC — a great LTV:CAC ratio with a 36-month payback creates serious cash flow strain for early-stage companies.
Segment CAC by acquisition channel — organic search, paid search, direct sales, and partner channels typically have very different CACs and LTV profiles.

Enterprise SaaS companies (ACV > 25,000) typically have CACs of 20,000–100,000+ due to long sales cycles and high-touch sales teams.
Self-serve SaaS products (ACV < 5,000) typically target CACs of 100–1,000 with payback under 12 months.
The average SaaS company spends approximately 80–120% of first-year revenue on customer acquisition — meaning CAC payback is typically 12+ months even for efficient businesses.

Common mistakes to avoid

Using only direct ad spend as the cost input — sales team salaries, commissions, and marketing overhead are real acquisition costs and must be included for accurate CAC.
Comparing CAC across different time periods without adjusting for sales cycles — enterprise deals may take 6–18 months to close; matching costs to the period of acquisition is complex.

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.

Frequently Asked Questions

What costs should I include in CAC?

Everything: paid ad spend, organic marketing salaries, SEO tools, agency fees, sales team salaries and commissions, CRM costs, and any marketing overhead.

What is a good LTV:CAC ratio?

3:1 is the widely-cited minimum benchmark. Below 1:1 means you're destroying value. Above 5:1 often means you're under-investing in growth.

How do I calculate LTV?

LTV = Average Purchase Value × Purchase Frequency × Average Customer Lifespan. For subscriptions: LTV = Average MRR per customer ÷ Monthly Churn Rate.