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Customer Lifetime Value (LTV) Calculator
Calculate how much a customer is really worth over their lifetime — then see exactly what raises it most. Free, private, no sign-up.
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What a customer is actually worth
Lifetime value decides what you can afford to spend acquiring anyone. Get it wrong and every downstream number is wrong with it — your CAC target, your payback period, your channel decisions.
Four inputs and a margin. The margin is the one that changes the answer most.
Revenue LTV flatters. Use gross profit.
This is the single most common error in the whole of unit economics, and it is not a small one — at a 72% margin the revenue figure overstates the real value by roughly a third.
- Revenue LTV = order value × frequency × lifespan. It ignores the cost of delivering the thing.
- Gross-profit LTV multiplies that by your margin, and is the figure every downstream decision should use.
- Quoting revenue LTV against a fully loaded CAC compares two numbers that were never measured the same way.
Lifespan is where optimism creeps in
The other input people overstate. A young company projecting a five-year customer lifespan has no data that supports it — it has a hope, and the LTV it produces is a hope too.
- Use a lifespan your retention numbers actually support. If you have twelve months of data, do not project five years.
- Lifespan is the inverse of churn: 1 ÷ monthly churn gives you the average, in months.
- At 5% monthly churn that is 20 months, not the 60 the deck assumed.
- 1Average order valueWhat they spend each time.
- 2Purchase frequencyOrders per year.
- 3LifespanFrom your churn, not your hopes.
- 4Gross marginThe step most people skip.
What the number is for
LTV on its own means very little. It becomes useful the moment you put it against what a customer costs to acquire.
- Aim for an LTV:CAC of at least 3:1. The worked example above sits at 7.9:1 against a $455 CAC.
- A very high ratio usually means under-investment in growth rather than a triumph — you could afford to acquire more aggressively.
- Check the payback period as well. A strong ratio with a 20-month payback still consumes cash faster than it makes it.
Your figures stay in your browser
Order values, margins and retention are not numbers most people want to type into a random website.
- The calculation runs in the page you are looking at.
- Which means your real figures can go in rather than rounded stand-ins.
- No account, and nothing kept afterwards.
Four numbers worth keeping
Why Parix.ai gives this away
We build subscription products, and almost every unit-economics argument we have sat through started with two people using different definitions of LTV. These tools are the same checks we run before quoting, which is why there is no paywall.
Work out my LTVWho uses it
Founders sizing what they can spend on acquisition, growth leads justifying budget, and investors reading unit economics from the outside.
It feeds these
Put it against cost with the CAC Calculator and the LTV:CAC Ratio Calculator. The lifespan input comes from the Churn Rate Calculator.
When LTV is the thing to move
Lifting retention raises LTV for every customer you already have, not just future ones. Our product team works on that end of it.