Given an average revenue per customer, a gross margin, and a customer lifespan or monthly churn rate, what is the gross and margin-adjusted lifetime value — and does the entered lifespan align with what the churn rate implies?

This tool is for: SaaS and subscription founders computing LTV to benchmark it against customer acquisition cost and set acquisition budget ceilings · E-commerce operators estimating how much each customer is worth over their buying lifetime to inform retention spend decisions · Anyone who needs to convert a churn rate into an implied customer lifetime and compare it against the lifespan used in an LTV model

Gross lifetime value — total revenue expected from a customer over their average lifespan
Margin-adjusted LTV — the gross lifetime value scaled down to the portion retained after cost of goods sold
Churn-implied customer lifetime — the average lifetime implied by the monthly churn rate alone
A comparison note between the entered lifespan and the churn-implied lifespan, flagging consistency between the two inputs

Average Revenue per Customer (per Month) The average monthly recurring revenue or average order value per customer. For subscription businesses, use the monthly subscription fee or ARPU. For transactional businesses, use average order value divided by average purchase frequency per month. Must be positive to compute LTV outputs.

Gross Margin (%) The gross margin percentage — revenue minus cost of goods sold, divided by revenue. For SaaS businesses this is typically 60–80%. For physical e-commerce it is typically 20–50%. Enter 100 if you want to compute gross LTV only and do not have a reliable margin figure.

Average Customer Lifespan (Months) The estimated number of months the average customer remains active. For subscription businesses, this can be derived from historical cohort data or estimated from the churn rate (1 / monthly churn rate). Enter the lifespan you use in your business model — the calculator will compare it against the churn-implied lifetime as a consistency check.

Monthly Churn Rate (%) The percentage of customers who stop being customers each month. A 4% monthly churn rate means 4 out of every 100 customers leave per month, implying an average lifetime of 25 months. Enter 0 if churn data is unavailable — the churn-implied lifetime output will be undefined and the comparison note will reflect this.

Formulas Used

Gross Lifetime Value

Gross LTV = Average Revenue per Customer × Average Customer Lifespan (Months)

Where: Average Revenue per Customer = Monthly recurring revenue or order value per customer (USD), Average Customer Lifespan = Expected number of months a customer remains active (months)

Source: HubSpot — Customer Lifetime Value (CLV) definition and formula

Margin-Adjusted LTV

Margin-Adjusted LTV = Gross LTV × (Gross Margin % / 100)

Where: Gross LTV = Total expected revenue per customer over their lifetime (USD), Gross Margin % = Revenue minus COGS, divided by revenue, expressed as a percentage (%)

Source: OpenStax — Principles of Accounting, Volume 2: Managerial Accounting

Churn-Implied Customer Lifetime

Estimated Lifetime (Months) = 1 / (Monthly Churn Rate / 100)

Where: Monthly Churn Rate = Percentage of customers who leave each month; must be greater than zero (%), Estimated Lifetime = Average months a customer is retained under a constant churn assumption (months)

Source: HubSpot — Customer Lifetime Value (CLV) definition and formula

Key Insight

On $50/month revenue per customer, 24-month lifespan, and 70% gross margin: gross LTV is $1,200 and margin-adjusted LTV is $840. A 4% monthly churn implies a 25-month lifetime — close to the entered 24 months, so the inputs are consistent. If margin drops from 70% to 50%, margin-adjusted LTV falls from $840 to $600 — a 28% drop for a 20-point margin change. The margin multiplier amplifies both improvements and deteriorations, making gross margin the highest-leverage input in the LTV model for businesses with variable COGS.

Frequently Asked Questions

What is the difference between gross LTV and margin-adjusted LTV?

Gross LTV is the total revenue a customer is expected to generate over their lifetime — it does not subtract any costs. Margin-adjusted LTV scales gross LTV by the gross margin percentage, giving the portion of that revenue the business retains after paying for the cost of goods sold. For acquisition decisions, margin-adjusted LTV is the correct figure: it represents the economic value the business actually captures, not just the cash that flows through. A business with a 40% gross margin and a $1,000 gross LTV retains only $400 to cover all other costs including customer acquisition. Using gross LTV in an LTV:CAC comparison will overstate the business case for acquisition spend.

How do I interpret the relationship between the entered lifespan and the churn-implied lifetime?

The churn-implied lifetime is what the entered monthly churn rate mathematically predicts the average customer lifespan will be — it's 1 divided by the monthly churn rate. If you entered a 4% monthly churn rate, the model implies a 25-month average lifetime. If the entered lifespan is 24 months, the two are nearly consistent. If the entered lifespan is 48 months but churn implies 25, the LTV is roughly double what the churn data supports. Either the lifespan assumption is based on different evidence (cohort data showing unusually long retention) or it is optimistic. The note output makes this discrepancy visible so the user can judge which input to trust.

Why is margin-adjusted LTV null when revenue per customer is zero?

LTV requires a positive revenue per customer and a positive lifespan as denominators or multipliers. When either is zero or negative, the resulting LTV is zero or undefined — there is no economic value to compute. The calculator returns null to flag this clearly rather than produce a misleading zero or infinity. The churn-implied lifetime is still computed when revenue is zero, because that output depends only on the churn rate, not on the revenue or lifespan inputs.

About This Calculator

Sources:

HubSpot — How to Calculate Customer Lifetime Value — Standard formula for customer lifetime value, the gross and margin-adjusted variants, the churn-rate-to-lifetime conversion, and how LTV is used alongside CAC in go-to-market unit economics
OpenStax — Principles of Accounting, Volume 2: Managerial Accounting — Peer-reviewed open academic textbook (Rice University) covering gross margin computation and the relationship between revenue, cost of goods sold, and retained margin used in the margin-adjusted LTV formula

Limitations:

Assumes constant average revenue per customer — does not model revenue expansion, upsell, downsell, or seasonal variation
Assumes constant monthly churn — a geometric decay model; actual churn often varies by cohort age, segment, and economic conditions
Does not discount future cash flows — LTV here is a nominal figure, not a net present value
Churn-implied lifetime assumes a memoryless exponential decay model; if churn is front-loaded (high early-tenure churn) or back-loaded, the formula may over- or underestimate average lifetime
Gross margin is entered as a single percentage — product-mix changes, volume discounts, and returns that shift margin over the customer lifetime are not modeled

When to consult a professional: Before using LTV in fundraising documents, investor presentations, or acquisition channel budget commitments where definitional consistency, cohort precision, and NPV discounting may be required by the audience

This calculator estimates customer lifetime value using a simple average-revenue and fixed-lifespan model. It does not model cohort-level churn variation, revenue expansion, upsell, discounting, or the time value of money. LTV is a planning metric — actual lifetime value per customer will vary across cohorts, segments, and time periods. This tool does not constitute business or financial advice.