LTV:CAC Ratio Calculator
Every $1 of acquisition cost returns $4.00 in lifetime value, a healthy 3:1 or better.
What is LTV:CAC ratio?
The LTV:CAC ratio is customer lifetime value (LTV) divided by customer acquisition cost (CAC), the single fastest read on whether your unit economics work.
A ratio of 4:1 means each customer returns four times in lifetime value what it cost to win them. Below 1:1 you lose money on every acquisition; the more headroom above 1, the more you have to cover overhead and fund growth.
Because it folds both sides of the equation into one number, it is the metric investors and operators reach for first when judging the health of a growth business.
How to calculate LTV:CAC ratio
LTV:CAC = LTV ÷ CAC
- Work out lifetime value. Estimate LTV as average order value times orders per year times customer lifespan. The example uses 720.
- Work out acquisition cost. Divide total sales and marketing spend by the new customers it won. The example uses 180.
- Divide LTV by CAC. 720 divided by 180 is 4.0, so the ratio is 4.0:1.
- Read it against 3:1. At or above 3:1 the economics are healthy; 1:1 to 3:1 is thin; below 1:1 you are losing money per customer.
Worked example
A customer is worth 720 in lifetime value and costs 180 to acquire.
| Customer lifetime value | $720 |
|---|---|
| Customer acquisition cost | $180 |
| Result | 4.0:1 · Healthy |
Every 1 of acquisition spend returns 4 in lifetime value, comfortably above the 3:1 convention. There is room to spend more aggressively on acquisition before the economics tighten.
What is a good LTV:CAC ratio?
The 3:1 rule of thumb is the most widely used health check for a growth business. It is a convention that tends to hold across subscription and ecommerce models, not a number the maths forces.
| LTV:CAC ratio | Read |
|---|---|
| unprofitable below 1:1 | You spend more to win a customer than they are worth |
| thin 1:1 to 3:1 | Profitable on acquisition but little left to fund growth |
| healthy 3:1 or better | The common target: enough headroom to profit and reinvest |
| under-investing above ~5:1 | Often a sign you could spend more and win more, profitably |
These bands are conventions, not laws, and the right level depends on margin, payback and how fast you want to grow. A high ratio is a prompt to test more spend, not a ceiling to defend.
How to improve LTV:CAC ratio
- Raise LTV by lifting order value, purchase frequency or lifespan, which widens the ratio without touching spend.
- Lower CAC by improving conversion and shifting budget to the cheapest channels that still convert.
- Cut churn: a longer-lived customer is worth more, so retention work moves the LTV side directly.
- If the ratio sits well above 5:1, test scaling acquisition spend before it falls back toward 3:1.
Frequently asked questions
- What is the LTV:CAC ratio?
- LTV:CAC is lifetime value divided by customer acquisition cost: how much a customer is worth over their lifetime against what it cost to win them. A 4:1 ratio means every 1 you spend acquiring a customer returns 4 in lifetime value. It is the fastest read on whether your unit economics work.
- What is a good LTV to CAC ratio?
- Around 3:1 is the common rule of thumb for a healthy growth business: you earn back about three times what you spend to acquire a customer, with room to cover overhead and fund growth. Under 1:1 you lose money on every customer; above about 5:1 you may be under-investing in growth. These are conventions, not laws.
- Why is 3:1 considered the golden ratio?
- At 1:1 you only break even on acquisition, before any other cost, so you need a multiple to cover overhead, support and the slow return of cash. Three times acquisition cost is the level most operators treat as enough headroom to profit and still reinvest. It is a convention that tends to hold across subscription and ecommerce businesses, not a number the maths forces.
- How do you calculate the LTV:CAC ratio?
- Divide lifetime value by customer acquisition cost. With an LTV of 720 and a CAC of 180, the ratio is 720 ÷ 180 = 4.0:1. Work out each input first if you need to: LTV is average order value times orders per year times customer lifespan; CAC is total acquisition spend divided by new customers won.
- Can the LTV:CAC ratio be too high?
- It can signal a missed opportunity. A very high ratio, above about 5:1, often means you are spending too little on acquisition and could win more customers profitably. Treat it as a prompt to test more spend, not a hard ceiling.