CAC & LTV Calculator
Customer acquisition cost, lifetime value, LTV:CAC and payback period.
How to use the CAC & LTV Calculator
- Enter your figures in the fields above — results update instantly as you type.
- Choose your currency symbol (the maths is the same in any currency).
- Use Share result to save a link that reloads your exact inputs, or Print for your records.
- Compare scenarios by changing one input at a time and noting how the main result moves.
Formula
CAC = Spend ÷ New customers LTV = (ARPU × Gross margin) ÷ Monthly churn Payback = CAC ÷ (ARPU × Gross margin)Worked example
CAC 150, ARPU 30 at 80% margin, 4% churn: LTV = 24 ÷ 0.04 = 600, LTV:CAC = 4×, payback 6.25 months.
Frequently asked questions
Why gross margin, not revenue?
Revenue overstates value; only gross profit can repay acquisition cost.
What churn should I use?
Use a recent cohort's monthly logo churn; blended numbers can hide weak cohorts.
Learn more
- Runway, Burn Rate and How Long Your Cash Really Lasts
- Unit Economics: The 7 Numbers Every Founder Should Know
Assumptions & limits
Results are estimates based on the inputs you provide and the formula shown, rounded for display. They do not account for every fee, tax rule or market condition. This tool is educational and is not financial, tax or legal advice — confirm important decisions with a qualified professional.
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