Customer Lifetime Value (LTV) Calculator

Understanding the customer lifetime value (LTV) calculator — concept and principle

Customer lifetime value (LTV or CLV) estimates how much a typical customer is worth to your business over the whole relationship, not just on the first order. Businesses use it to decide how much they can afford to spend to win a customer and whether retention work pays off. The calculator works with any currency; the example below uses US dollars.

How it is calculated

The calculator uses the simple, non-discounted model:

• LTV (revenue) = average order value × purchases per year × customer lifespan (years)
• LTV (gross profit) = LTV (revenue) × gross margin ÷ 100
• Yearly gross profit per customer = average order value × purchases per year × gross margin ÷ 100

Gross margin is the share of each sale left after direct costs; lifespan is how many years a customer usually keeps buying.

The principle

LTV is a stream of future purchases added together. Revenue alone overstates value because each sale carries direct costs, so the headline figure is based on gross profit: the money each customer actually contributes toward marketing, overheads and profit. This version treats every year as equal and does not discount future money. More advanced models apply a discount rate and a retention (churn) curve, which give a lower, more realistic value when lifespans are long.

Worked example

1. Inputs: average order $60, 4 purchases per year, 45% gross margin, 3-year lifespan.
2. Revenue per year: 60 × 4 = $240.
3. Yearly gross profit: 240 × 0.45 = $108.00.
4. LTV (revenue): 240 × 3 = $720.00.
5. LTV (gross profit): 720 × 0.45 = $324.00, the main result.

How to read the result

Compare gross-profit LTV with your customer acquisition cost (CAC). A ratio of about 3:1 is a commonly quoted rule of thumb for a healthy business; a ratio near 1:1 means you barely recover what you spend to win a customer. In this example, spending more than about $324 to acquire a customer would lose money over the customer's life, before overheads. Raising order value, purchase frequency, margin or retention each lifts LTV in direct proportion.

Common mistakes

• Using revenue LTV instead of gross-profit LTV when comparing with acquisition cost.
• Guessing lifespan from a short history; new businesses rarely know true retention yet.
• Mixing segments with very different behaviour into one average.

Frequently asked questions

What is a good LTV to CAC ratio?

Around 3:1 is a widely used benchmark, but the right level depends on your cash position, payback period and growth goals.

How do I estimate customer lifespan?

A common shortcut is 1 ÷ annual churn rate. If 25% of customers stop buying each year, the average lifespan is about 4 years.

Should LTV include shipping and payment fees?

Yes, if they are direct costs of each order. Include them in your gross margin so the result reflects real contribution.

Sources: Gupta, S. & Lehmann, D. R., Managing Customers as Investments, Wharton School Publishing, 2005 · Kotler, P. & Keller, K. L., Marketing Management, Pearson