Glossary /
LTV/CAC Ratio
Efficiency & cost
LTV/CAC Ratio
The return on every dollar spent acquiring a customer—and why the famous 3:1 benchmark deserves a closer look.
Attribution & Measurement
Unit Economics
Data Governance & Nomenclature
Creative & Delivery
Audiences & Targeting
Mobile & Privacy
LTV/CAC Ratio measures how much lifetime value a customer generates relative to what it cost to acquire them.
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What is LTV/CAC Ratio?
LTV/CAC Ratio is the headline efficiency number for any acquisition engine. It divides what a customer is worth over their lifetime by what you paid to win them. A ratio above 1 means customers earn back more than they cost; the higher the ratio, the more efficient the engine—up to a point. It's the metric boards reach for because it compresses a whole growth model into one figure. But it hides timing entirely: a strong ratio built on a 30-month payback can still starve a business of cash. Read it alongside CAC Payback Period, never alone. Neither input is platform-reported. LTV comes from your retention and margin data; CAC from total spend over new customers. Ad platforms report cost per conversion, not return on lifetime value—so the ratio is computed in your data, using definitions you control.
LTV/CAC Ratio formula
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost. Use the same basis for both: if LTV is margin-based, CAC should be fully-loaded. Mixing revenue-based LTV with media-only CAC inflates the ratio. Both inputs come from your own data—LTV from order value, frequency, lifespan, and margin; CAC from total sales and marketing spend over new customers.
Worked example
Blended unit economics.
LTV
$1,500
CAC
$500
LTV/CAC Ratio
3.0 (3:1)
$1,500 ÷ $500 = 3.0
The “3:1 is healthy” rule is a rule of thumb, not a law — it depends on margin, payback, and growth stage.
LTV/CAC Ratio formula
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost. Use the same basis for both: if LTV is margin-based, CAC should be fully-loaded. Mixing revenue-based LTV with media-only CAC inflates the ratio. Both inputs come from your own data—LTV from order value, frequency, lifespan, and margin; CAC from total sales and marketing spend over new customers.
Worked example
Blended unit economics.
LTV
$1,500
CAC
$500
LTV/CAC Ratio
3.0 (3:1)
$1,500 ÷ $500 = 3.0
The “3:1 is healthy” rule is a rule of thumb, not a law — it depends on margin, payback, and growth stage.
How LTV/CAC Ratio differs across ad platforms
Your CRM / Warehouse
Both inputs originate here and in finance. LTV comes from retention and margin; CAC from total spend over new customers. The ratio is assembled downstream, not in any ad tool.
Google Ads
Reports CPA and conversion value, which feed CAC and value-based bidding. It cannot compute LTV/CAC—it has no view of lifetime value or fully-loaded acquisition cost.
Meta Ads
Reports cost per result and purchase value. Useful as inputs, but Meta can't see customer lifespan or total cross-channel spend, so it never reports the ratio itself.
Common LTV/CAC Ratio misconceptions
3:1 is the universal target for a healthy business.
The 3:1 rule is a rough heuristic, not a law. The right ratio depends on margin, payback speed, growth stage, and capital cost. A very high ratio can even signal underinvestment in acquisition—leaving growth on the table.
A strong LTV/CAC ratio means the business is healthy.
The ratio ignores timing. A 4:1 ratio with a 24-month payback can still cause a cash crunch. Always pair LTV/CAC with CAC Payback Period to see both return and recovery speed.
Frequently Asked Questions
What is LTV/CAC Ratio in simple terms?
LTV/CAC Ratio tells you how many dollars of lifetime value you get for each dollar spent acquiring a customer. A 3:1 ratio means a customer is worth three times what you paid to win them.
How is LTV/CAC Ratio calculated?
Why does LTV/CAC Ratio differ across ad platforms?
How does Clarisights report on LTV/CAC Ratio?
Attribution & Measurement
Unit Economics
Data Governance & Nomenclature
Creative & Delivery
Audiences & Targeting
Mobile & Privacy
LTV/CAC Ratio measures how much lifetime value a customer generates relative to what it cost to acquire them.
?
?
What is LTV/CAC Ratio?
LTV/CAC Ratio is the headline efficiency number for any acquisition engine. It divides what a customer is worth over their lifetime by what you paid to win them. A ratio above 1 means customers earn back more than they cost; the higher the ratio, the more efficient the engine—up to a point. It's the metric boards reach for because it compresses a whole growth model into one figure. But it hides timing entirely: a strong ratio built on a 30-month payback can still starve a business of cash. Read it alongside CAC Payback Period, never alone. Neither input is platform-reported. LTV comes from your retention and margin data; CAC from total spend over new customers. Ad platforms report cost per conversion, not return on lifetime value—so the ratio is computed in your data, using definitions you control.
LTV/CAC Ratio formula
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost
LTV/CAC Ratio = Customer Lifetime Value ÷ Customer Acquisition Cost. Use the same basis for both: if LTV is margin-based, CAC should be fully-loaded. Mixing revenue-based LTV with media-only CAC inflates the ratio. Both inputs come from your own data—LTV from order value, frequency, lifespan, and margin; CAC from total sales and marketing spend over new customers.
Worked example
Blended unit economics.
LTV
$1,500
CAC
$500
LTV/CAC Ratio
3.0 (3:1)
$1,500 ÷ $500 = 3.0
The “3:1 is healthy” rule is a rule of thumb, not a law — it depends on margin, payback, and growth stage.
How LTV/CAC Ratio differs across ad platforms
Your CRM / Warehouse
Both inputs originate here and in finance. LTV comes from retention and margin; CAC from total spend over new customers. The ratio is assembled downstream, not in any ad tool.
Google Ads
Reports CPA and conversion value, which feed CAC and value-based bidding. It cannot compute LTV/CAC—it has no view of lifetime value or fully-loaded acquisition cost.
Meta Ads
Reports cost per result and purchase value. Useful as inputs, but Meta can't see customer lifespan or total cross-channel spend, so it never reports the ratio itself.
Common LTV/CAC Ratio misconceptions
3:1 is the universal target for a healthy business.
The 3:1 rule is a rough heuristic, not a law. The right ratio depends on margin, payback speed, growth stage, and capital cost. A very high ratio can even signal underinvestment in acquisition—leaving growth on the table.
A strong LTV/CAC ratio means the business is healthy.
The ratio ignores timing. A 4:1 ratio with a 24-month payback can still cause a cash crunch. Always pair LTV/CAC with CAC Payback Period to see both return and recovery speed.
Related Terms
Frequently Asked Questions
What is LTV/CAC Ratio in simple terms?
LTV/CAC Ratio tells you how many dollars of lifetime value you get for each dollar spent acquiring a customer. A 3:1 ratio means a customer is worth three times what you paid to win them.
How is LTV/CAC Ratio calculated?
Why does LTV/CAC Ratio differ across ad platforms?
How does Clarisights report on LTV/CAC Ratio?
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