CAC Calculator
Calculate customer acquisition cost (CAC), LTV:CAC ratio, and payback period. Find out if your marketing spend is profitable and how long to recoup each customer.
Reviewed for accuracy by Marcus Webb and the Blueprint Dynamics editorial team (last updated July 2026). Our calculators use primary-source formulas and are cross-checked against IRS publications, Fannie Mae guidelines, and Federal Reserve data. Learn more about our methodology.
CAC
$200.00
per customer
LTV:CAC Ratio
2.50x
Marginal
Payback Period
4.8 months
Total Customers
50
Benchmark: LTV:CAC of 3:1 or higher is considered healthy. Under 1:1 means you lose money on every customer.
What customer acquisition cost measures
Customer Acquisition Cost (CAC) is the average amount you spend to acquire one new paying customer. The basic formula: CAC = total sales and marketing spend / number of new customers acquired in the same period. A company that spent $50,000 on sales and marketing last month and acquired 200 new customers has a CAC of $250. CAC is the fundamental unit economics metric that determines whether growth is creating or destroying value — because every dollar of CAC must be recovered from the revenue each customer generates over their lifetime.
Fully-loaded CAC vs. blended CAC
The calculation of "sales and marketing spend" is where many companies mislead themselves. Blended CAC includes only direct ad spend. Fully-loaded CAC includes all costs associated with acquiring customers: advertising and paid media, sales team salaries and commissions, marketing team salaries, agency fees, sales tools and CRM costs, content and creative production, and events or trade shows. Fully-loaded CAC is always higher — often 2–4x the blended paid acquisition cost — and is the more honest number for evaluating business health. Investors always ask for fully-loaded CAC.
LTV:CAC ratio — the key benchmark
CAC in isolation is meaningless. The metric that matters is the ratio of customer lifetime value (LTV) to CAC. LTV = average revenue per customer per month × average customer lifespan × gross margin. For a SaaS business with $50/month average revenue, 24-month average retention, and 75% gross margin: LTV = $50 × 24 × 0.75 = $900. If CAC = $250, LTV:CAC = 3.6:1. The VC-standard threshold is 3:1 or higher for SaaS businesses. Below 1:1 means you lose money on every customer acquired. A ratio above 5:1 may indicate under-investing in growth — you're leaving money on the table by not acquiring more customers at an economically favorable rate.
CAC payback period
LTV:CAC alone doesn't capture time value. CAC payback period = CAC / (monthly recurring revenue per customer × gross margin). This tells you how many months it takes to recover your acquisition cost. A $250 CAC on $50 MRR at 75% margin: payback = $250 / ($50 × 0.75) = $250 / $37.50 = 6.7 months. Most investors want payback periods under 12 months for SaaS; under 6 months is considered excellent. Long payback periods require more working capital to fund growth, creating cash flow constraints even for fast-growing businesses.
How to reduce CAC
Four primary levers: (1) Improve conversion rates — the same ad spend delivers more customers. A 20% improvement in landing page conversion cuts CAC by ~17% with no change in spend. (2) Invest in organic channels — SEO, content marketing, referral programs, and word-of-mouth have near-zero marginal cost per customer once built. (3) Optimize channel mix — allocate more spend to lowest-CAC channels and cut or reduce highest-CAC channels. (4) Improve lead quality at top of funnel — better targeting produces higher-quality leads that convert more often, reducing cost per converted customer even if cost per lead stays constant.