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SaaS Unit Economics
Compute contribution margin, LTV, LTV:CAC, payback months, and magic number from CAC, ARPU, gross margin, and monthly churn.
- 1Fill inputs
- 2Run
- 3Copy / export
Inputs
Required fields on the left
Results
Appears after you run
CAC, LTV, payback
Enter acquisition cost, ARPU, margin, and churn to see LTV:CAC and payback months.
From inputs to a decision
Compute contribution margin, LTV, LTV:CAC, payback months, and magic number from CAC, ARPU, gross margin, and monthly churn.
- 01
Enter CAC, ARPU, margin, and churn.
- 02
Optionally add sales & marketing spend and net new ARR.
- 03
Read LTV:CAC and payback.
Tips for better results
- Use monthly churn as a decimal (3% → 0.03).
- Use after-tax numbers when comparing job vs side income.
- Monte Carlo outputs are probabilities, not guarantees.
Frequently asked questions
- How is LTV calculated?
- LTV = (ARPU × gross margin) ÷ monthly churn.
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