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Marketing ROI Calculator (CAC and LTV)

Enter your spend and unit economics to see customer acquisition cost, lifetime value, the LTV:CAC ratio, and how long it takes to earn back what you paid to acquire a customer.

Your numbers

Results

CAC

$200

Cost to acquire one customer

LTV

$1,600

Avg lifetime 20.0 mo

LTV:CAC ratio

8.0:1

Healthy (3:1 or better)

CAC payback

2.5 mo

Under 12 months is the common B2B target

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HubSpot Marketing Analytics

Track CAC and LTV automatically across every channel instead of rebuilding this spreadsheet each quarter.

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How this is calculated

  • CAC = monthly marketing spend / new customers per month.
  • Average lifetime (months) = 100 / monthly churn percent.
  • LTV = ARPU x gross margin x average lifetime.
  • LTV:CAC = LTV / CAC. CAC payback = CAC / (ARPU x gross margin).

The 3:1 LTV:CAC benchmark and the 12 month payback target are widely cited B2B SaaS heuristics (see the writing of David Skok and the OpenView SaaS benchmarks). Treat them as guardrails, not laws. This model assumes flat churn and margin, which real cohorts rarely deliver, so use it to compare scenarios rather than to forecast to the dollar.

Frequently asked questions

What is a good LTV:CAC ratio?

Most B2B operators aim for 3:1 or better. Below 1:1 you lose money on every customer. Far above 5:1 often means you are underinvesting in growth.

How is customer lifetime estimated?

Lifetime in months is 1 divided by your monthly churn rate. At 5 percent monthly churn the average customer stays 20 months. It is a simplification that ignores cohort effects.

Should CAC include salaries and tools?

For a fully loaded CAC, yes. This calculator uses whatever you enter as monthly spend, so include paid media, agency fees, and headcount if you want the honest number.