SaaS Unit Economics Calculator
Calculate SaaS LTV, LTV/CAC ratio and CAC payback from ARPU, gross margin, monthly churn and customer acquisition cost.
SaaS unit economics explain whether customer acquisition creates value. This calculator estimates gross profit per customer, lifetime value, LTV/CAC ratio and CAC payback from monthly ARPU, gross margin, churn and customer acquisition cost.
Calculate your result
Change the inputs on the left. Results update instantly on the right.
Unit economics inputs
Why use the SaaS Unit Economics Calculator
Growth is useful only when the economics behind each customer make sense. A high LTV/CAC ratio suggests acquisition can scale profitably. A long CAC payback period means cash is locked for too long before the customer repays acquisition cost. This calculator gives founders and operators a quick read on both metrics.
Benefits at a glance
LTV/CAC ratio
Measure how much lifetime gross profit is created for every rupee spent acquiring a customer.
CAC payback
Estimate the number of months needed to recover acquisition cost from gross profit.
Churn sensitivity
See how lower churn can materially improve lifetime value.
How to use the SaaS Unit Economics Calculator
- 1
Enter ARPU
Use average monthly revenue per customer or account.
- 2
Enter gross margin
Use revenue after hosting, support and delivery costs.
- 3
Enter monthly churn
Use logo churn or account churn for the customer cohort.
- 4
Enter CAC
Include sales and marketing cost per acquired customer.
Worked example
B2B SaaS example
A product has Rs 2,000 ARPU, 80 percent gross margin, 3 percent monthly churn and Rs 8,000 CAC.
- Gross profit
- Rs 1,600 per month
- LTV
- About Rs 53,333
- LTV/CAC
- About 6.7x
- CAC payback
- 5 months
Assumptions and exclusions
- LTV is calculated as monthly gross profit divided by monthly churn.
- The calculator does not model expansion revenue, contraction, discounting or cohort-specific retention curves.
- Use consistent customer definitions across ARPU, churn and CAC.
Frequently asked questions
What is a good LTV/CAC ratio?
Many SaaS teams look for 3x or higher, but the right benchmark depends on market, retention, gross margin and sales cycle.
What is CAC payback?
CAC payback is the number of months needed to recover customer acquisition cost from gross profit generated by that customer.
Should I use revenue or gross profit for LTV?
Gross profit is usually better because hosting, support and delivery costs reduce the value of revenue.
Does this include expansion revenue?
No. This is a simple steady-state model. Expansion revenue should be added in a more detailed cohort model.
Final word
Use the SaaS unit economics calculator before scaling paid acquisition or sales hiring. Healthy growth needs both strong LTV/CAC and a CAC payback period that the company's cash balance can support.
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