How do you calculate LTV:CAC ratio?

LTV:CAC = LTV divided by CAC. LTV = (ARPU x Gross Margin) / Monthly Churn Rate. CAC = Total Sales and Marketing Spend / New Customers Acquired. For example, if LTV is $1,980 and CAC is $589, the ratio is 3.4:1.

What Is a Good LTV:CAC Ratio? Formula & Benchmarks

Q: What is a good LTV:CAC ratio?

A healthy LTV:CAC ratio is 3:1 or higher, meaning the lifetime value of a customer is at least three times the cost to acquire them. Below 1.5:1 is unsustainable. Above 5:1 may mean you are under-investing in growth.

Q: Why is a very high LTV:CAC ratio bad?

A ratio above 5:1 may seem great but could indicate you are under-investing in growth and leaving market share on the table. Investors prefer 3:1 to 5:1 because it signals both healthy unit economics and a commitment to growing the customer base.

The LTV:CAC ratio compares the lifetime value of a customer (LTV) to the cost of acquiring them (CAC). It is the ultimate unit economics sanity check for any SaaS business. A ratio of 3:1 means you generate three dollars of value for every dollar spent on acquisition.

Quick Answer

Healthy LTV:CAC = 3:1 or higher

Below 1.5:1 = unsustainable. Above 5:1 = under-investing in growth.

How to Calculate LTV and CAC

Before you can calculate the ratio, you need both components:

LTV Formula

LTV = (ARPU × Gross Margin) ÷ Monthly Churn Rate

Example: ARPU = $99, gross margin = 80%, monthly churn = 4%. LTV = ($99 × 0.80) ÷ 0.04 = $1,980

CAC Formula

CAC = Total Sales & Marketing Spend ÷ New Customers Acquired

Example: $16,500 total S&M spend, 28 new customers. CAC = $16,500 ÷ 28 = $589

LTV:CAC Ratio

$1,980 ÷ $589 = 3.4:1

What Is a Good LTV:CAC Ratio?

Ratio	Verdict	What It Means
Below 1.5:1	Unsustainable	Spending too much to acquire customers relative to their value
1.5:1 to 3:1	Caution	Workable but thin margins; improve LTV or reduce CAC
3:1 to 5:1	Healthy	Strong unit economics with room to invest in growth
Above 5:1	Under-investing	Leaving market share on the table; spend more on acquisition

Why Above 5:1 Is Not Always Good

A ratio above 5:1 may seem great — you are generating a lot of value per acquisition dollar. But it often means you are under-investing in growth and leaving market share on the table. Investors prefer 3:1 to 5:1 because it signals both healthy unit economics and a commitment to growing the customer base. If your ratio is above 5:1, consider increasing your sales and marketing spend to accelerate growth while the ratio is still strong.

How to Improve Your LTV:CAC Ratio

You can improve the ratio from either side: increase LTV or decrease CAC. The most effective approaches:

Increase LTV

Reduce churn — even a 1% improvement compounds significantly
Raise prices — a 10% increase directly flows to LTV
Drive expansion revenue through upsells and cross-sells
Improve gross margin by reducing infrastructure costs

Decrease CAC

Shift spend toward efficient channels (organic, referrals, PLG)
Improve conversion rates on your pricing and signup pages
Focus on customer segments with shorter sales cycles
Align sales and marketing on lead quality definitions

Track LTV:CAC by Channel

A blended LTV:CAC across all channels can be misleading. A blended 3:1 ratio might hide the fact that one channel is 6:1 while another is 1:1. Track LTV:CAC by acquisition channel and cohort to identify which efforts are actually profitable, and reallocate spend toward efficient channels.

Common LTV:CAC Mistakes

Common Mistake

Using revenue instead of gross profit to calculate LTV. LTV should reflect gross margin — if your ARPU is $100 but gross margin is 70%, the customer generates $70 of gross profit per month, not $100. Using revenue overstates LTV and makes your unit economics look better than they are.