Business calculator

Free customer acquisition cost (cac) calculator

Enter your sales and marketing spend and new customers acquired — this customer acquisition cost calculator returns CAC, payback period, and the LTV/CAC ratio, updated live, as you type.

InputsLive
Investment cost
$
Total gain (revenue / proceeds)
$
Include the original investment amount if it was returned.
Annual cash flow (for payback)
$/yr
Optional. Used to calculate simple payback period.
Result
ROI
50%
Net gain: $2,500 · Payback: 2.5 yrs
ROI50%
Net gain$2,500
Total gain$7500
Payback2.5 yrs

ROI = (gain − cost) ÷ cost × 100. This is simple ROI and does not account for time value of money.

Results are estimates. Consult a professional.

How it's calculated

How the customer acquisition cost calculator works

Customer acquisition cost (CAC) is the total amount your business spends to acquire a single new customer during a given period. It combines every dollar invested in marketing and sales — ad spend, agency fees, salaries of customer-facing staff, tools, and events — then divides by the number of new customers won.

Two variants matter: blended CAC includes fully-loaded sales and marketing headcount costs, giving a true economic picture; paid CAC counts only direct ad spend, useful for measuring campaign efficiency. Both should be tracked together.

CAC = (total sales spend + total marketing spend) ÷ new customers acquired in period
CAC payback period (months) = CAC ÷ (average monthly revenue per customer × gross margin %)
LTV / CAC ratio = customer lifetime value ÷ CAC
For Entrepreneurs — SaaS Metrics 2.0: A Guide to the Metrics That Matter
Example

Worked example: SaaS startup in Q1

Example: $130,000 total spend, 260 new customers

A B2B SaaS company spent $50,000 on paid ads and $80,000 on sales team salaries in Q1. They acquired 260 new customers during the same quarter. Monthly recurring revenue per customer averages $42, and gross margin is 72%.

Blended CAC = ($50,000 + $80,000) ÷ 260 = $500
Paid CAC = $50,000 ÷ 260 = $192
Monthly margin per customer = $42 × 72% = $30.24
CAC payback = $500 ÷ $30.24 ≈ 16.5 months
$500
Blended CAC. With an LTV of ~$1,800 (at 72% margin over 3 years), the LTV/CAC ratio is 3.6× — within the healthy range for SaaS.
Quick reference

CAC payback period by CAC and monthly margin

CAC payback period tells you how many months of gross profit it takes to recover the cost of acquiring a customer. A payback under 12 months is considered healthy for most SaaS businesses; under 6 months is strong. E-commerce targets payback within the first order or season.

CAC$20 / mo Margin$50 / mo Margin$200 / mo Margin
$1005 months2 months< 1 month
$30015 months6 months1.5 months
$1,00050 months20 months5 months

Source: SaaS benchmarks (David Skok, For Entrepreneurs); months rounded to one decimal

Practical tips

Tips for reducing and benchmarking CAC

CAC is most useful as a trend metric and as one half of the LTV/CAC ratio. A rising CAC is not necessarily bad if LTV is rising faster — the ratio is what matters for unit economics.

  • Target LTV/CAC ≥ 3× — below 3× the business is likely destroying value per customer; above 5× may signal under-investment in growth.
  • Track CAC by channel separately — blended CAC hides the fact that organic/SEO customers might cost $50 while paid-search customers cost $800; optimise the mix accordingly.
  • Include the full sales cycle lag — match marketing spend from the quarter in which leads were generated to customers who closed from those leads, not the close quarter.
  • Benchmark against industry norms — SaaS CAC typically runs $200–$500, e-commerce $50–$150, retail $10–$30; materially higher CAC demands a corresponding LTV advantage.
  • Invest in onboarding to reduce churn — cutting churn rate extends customer lifetime, raises LTV, and therefore tolerates a higher CAC while preserving healthy unit economics.
Accuracy & limits

Accuracy and limitations

CAC calculations are only as good as the period alignment between spend and new customers. Attribution is rarely perfect — a customer who clicked a paid ad, read three blog posts, and attended a webinar before signing up defies clean single-channel attribution. Blended CAC sidesteps this by treating all spend as a pool, which is conservative and honest.

This calculator is for educational and planning purposes only and does not constitute financial or investment advice. Industry benchmarks vary widely by market segment, deal size, and sales cycle length. Not financial advice — consult a financial advisor or CFO before making headcount or budget decisions based on CAC modeling.

Glossary

CAC and growth metric terms defined

Total sales and marketing spend divided by the number of new customers acquired in the same period. Measures the average cost to win one customer.
CAC calculated using fully-loaded costs including all salaries, tools, events, and overhead for both sales and marketing teams — the most complete and conservative measure.
CAC calculated using only direct advertising spend, excluding headcount. Useful for evaluating campaign efficiency but understates the true cost of customer acquisition.
The number of months of gross profit needed to recover the acquisition cost of one customer. Calculated as CAC divided by monthly recurring revenue per customer multiplied by gross margin.
Customer lifetime value divided by customer acquisition cost. A ratio of 3× or above is generally considered healthy; below 1× indicates the business loses money on every customer acquired.
Predictable, recurring revenue billed each month — the primary revenue metric for subscription businesses and a key input to CAC payback period calculations.
Revenue minus cost of goods sold (or cost of service delivery), expressed as a percentage of revenue. Used in CAC payback to ensure only profit — not revenue — is credited toward recovering acquisition costs.
About

About this customer acquisition cost calculator

This calculator runs entirely in your browser — nothing you enter is sent to any server.

Browse more in our business calculators, or explore the complete library on the free calculators page.

Questions

Frequently asked questions about the free customer acquisition cost (cac) calculator

A customer acquisition cost (CAC) calculator is a free online tool that helps you calculate cost to acquire a new customer from sales/marketing spend. Total sales + marketing spend ÷ new customers in the period. It runs entirely in your browser with instant results and no sign-up.
No — these calculators provide quick estimates for planning and decisions. For tax filings, financial reporting, or formal valuations, use a CPA / CFA.
Most ratios assume GAAP figures from financial statements. For cash-basis or tax-basis filings, adjust the inputs accordingly.
Core finance formulas (DCF, IRR, depreciation methods, payment math) are stable. Tax-specific calculators (like-kind, repossession) reflect post-TCJA / 2025 rules where applicable.

Want a calculator built for your business?

Customize any of our 400+ tools to match your brand, or commission a new one tailored to how your business actually calculates — pricing, payroll, quotes, anything. Deployed on your domain, math runs in your visitors' browsers.