Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Lifetime value
$1,983
LTV : CAC ratio
3.20
Average lifespan (months)
28.6
CAC payback (months)
8.9
Read
Healthy unit economics
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter average revenue per user ($/mo).
- 2Enter gross margin (%).
- 3Enter monthly churn rate (%).
- 4Enter cac ($).
- 5Read your lifetime value on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
LTV is gross-margin dollars, not revenue — counting revenue inflates it by whatever your delivery costs are. Healthy subscription businesses run an LTV:CAC of 3 or better.
Worked example
Using the values the calculator loads with:
Inputs
- Average revenue per user: 89 $/mo
- Gross margin: 78 %
- Monthly churn rate: 3.5 %
- CAC: 620 $
Results
- Lifetime value: $1,983.43
- LTV : CAC ratio: 3.2
- Average lifespan (months): 28.6
- CAC payback (months): 8.9
- Read: Healthy unit economics
What each field means
Inputs
- Average revenue per user ($/mo)
- The average revenue per user used in the calculation, measured in $/mo. Starts at 89 $/mo so you have a working example on load.
- Gross margin (%)
- The gross margin used in the calculation, measured in %. Starts at 78 % so you have a working example on load. Accepted range: 0–100 %.
- Monthly churn rate (%)
- The monthly churn rate used in the calculation, measured in %. Starts at 3.5 % so you have a working example on load. Accepted range: 0.01–100 %.
- CAC ($)
- The cac used in the calculation, measured in $. Starts at 620 $ so you have a working example on load.
Results
- Lifetime value
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- LTV : CAC ratio
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Average lifespan (months)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- CAC payback (months)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Read
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the customer lifetime value calculator work?
LTV is gross-margin dollars, not revenue — counting revenue inflates it by whatever your delivery costs are. Healthy subscription businesses run an LTV:CAC of 3 or better. The underlying maths is: Lifespan = 1 ÷ Monthly churn. LTV = ARPU × Gross margin × Lifespan.
What do I need to enter?
4 values: average revenue per user, gross margin, monthly churn rate, and cac. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the lifetime value result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Customer Lifetime Value Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/ltv
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/ltv" target="_blank" rel="noopener">Customer Lifetime Value Calculator — RevenueLab</a> (2026).</p>
Source: [Customer Lifetime Value Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/ltv) (2026).