CAC Calculator
Divide your total sales and marketing spend by the new customers you won to get your CAC, and see how many months of gross margin it takes to earn that cost back.
Reviewed by the CalcCafe editorial team · Last updated 18 July 2026 · How we test our tools
Example
Suppose you spend $20,000 on sales and $30,000 on marketing in a month and close 100 new customers. Total spend is $50,000, so CAC = 50,000 ÷ 100 = $500. If each customer pays $200 per month at an 80% gross margin, you earn $160 of margin per customer per month, so CAC payback = 500 ÷ 160 ≈ 3.1 months — comfortably inside the 12-month benchmark most SaaS investors look for.
How it works
CAC = (sales spend + marketing spend) ÷ new customers acquired in the same period. Payback months = CAC ÷ (monthly revenue per customer × gross margin ÷ 100), i.e. how many months of gross margin — not revenue — it takes to recover the acquisition cost. If any denominator is zero the tool returns 0 rather than an error. Use the same time window (usually a month or quarter) for both spend and customer counts.
Good to know
The number one CAC mistake is under-counting the numerator. A fully-loaded CAC includes everything it takes to win a customer: sales and marketing salaries with benefits, commissions, ad spend, agency and contractor fees, martech tools (CRM, analytics, email platforms), content production, events and free-trial hosting costs. Founders who only count ad spend routinely report a CAC two to four times lower than reality, and diligence teams will recompute it fully loaded — better to know the honest number first.
Distinguish blended CAC from paid CAC. Blended CAC divides all spend by all new customers, including organic and word-of-mouth signups. Paid CAC divides paid-channel spend by customers attributable to those channels only. Blended looks flattering while organic is strong, but it hides deteriorating paid efficiency: if paid CAC is climbing while blended stays flat, growth is being subsidised by a finite organic pool. Investors typically want to see both, plus CAC by channel.
Two benchmarks dominate SaaS conversations. First, LTV:CAC of at least 3:1 — you should earn at least three dollars of gross-margin-adjusted lifetime value per dollar of acquisition cost. Below 3:1 growth destroys capital; far above 5:1 you may be under-investing in growth. Second, CAC payback under 12 months for SMB-focused SaaS (18-24 months is tolerated for enterprise sales with high retention). Payback matters because it determines how much cash you must front to grow: a 36-month payback means every cohort ties up three years of spend before turning profitable.
CAC also behaves badly at scale. Early customers come cheap — founder networks, early adopters, low-competition keywords. As you saturate those pockets, marginal CAC rises even if average CAC still looks fine, which is why sophisticated teams track cohort-level and channel-level CAC monthly rather than a single blended annual figure. Model your growth plan with marginal CAC 20-50% above today’s average and you will rarely be unpleasantly surprised.
Frequently asked questions
What costs should I include in CAC?
Everything required to acquire a customer: sales and marketing salaries and commissions, ad spend, agency and contractor fees, marketing software, content and event costs. A fully-loaded CAC is usually 2-4x higher than ad spend alone, and it is the number investors will recompute during diligence.
What is the difference between blended and paid CAC?
Blended CAC divides all sales and marketing spend by all new customers, including organic signups. Paid CAC divides paid-channel spend by customers won through those channels. Track both: blended can look healthy while paid efficiency quietly deteriorates.
What is a good CAC payback period?
Under 12 months is the common benchmark for SMB and mid-market SaaS; enterprise businesses with very low churn can justify 18-24 months. Payback is measured in months of gross margin, not revenue, so a low gross margin lengthens it.
Is my data uploaded anywhere?
No — this calculator runs entirely in your browser. Your spend and customer figures never leave your device, and the page works offline once loaded.
People also ask
How do I calculate customer acquisition cost?
Add up all sales and marketing spend for a period and divide by the number of new customers acquired in the same period. For example, $50,000 of spend that wins 100 customers is a CAC of $500.
What is a good LTV to CAC ratio?
3:1 is the widely used floor for a healthy SaaS business — every dollar spent acquiring customers should return at least three dollars of gross-margin-adjusted lifetime value. Much above 5:1 may signal under-investment in growth.
How can I lower my CAC?
Improve conversion rates before adding spend, lean on channels with compounding returns (SEO, referrals, product-led growth), tighten your ideal customer profile so sales effort lands on better-fit leads, and cut channels whose channel-level CAC exceeds what your LTV supports.
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Sources & references
These tools follow our methodology and provide educational estimates only — verify important figures with a qualified professional.