Customer lifetime value (CLV, also LTV) is the total revenue — or profit — a customer generates from their first purchase through their last. It's the single most important metric for understanding whether your acquisition spend is sustainable.
The relationship between CLV and customer acquisition cost (CAC) determines the health of your growth model:
- CLV > 3× CAC — Generally healthy unit economics
- CLV ≈ CAC — Breakeven on acquisition; growth relies entirely on retention
- CLV < CAC — You're paying more to acquire customers than they're worth
Calculating CLV
Simple CLV:
CLV = Average Order Value × Purchase Frequency × Customer Lifespan
Example: A subscription product with $50 monthly revenue and an average 18-month lifespan:
CLV = $50 × 12 × 1.5 years = $900
Discounted CLV adjusts for the time value of money, reducing the weight of future revenue. Use this for multi-year customer relationships where capital costs matter.
CLV and CRO
CLV changes how you prioritize optimization work:
| CRO focus | Impact on CLV |
|---|---|
| Onboarding flow | Reduces early churn, extends lifespan |
| Upsell/cross-sell pages | Increases AOV and purchase frequency |
| Checkout optimization | Increases initial conversion |
| Email re-engagement | Recovers at-risk customers |
| Loyalty programs | Increases frequency and lifespan |
Optimizing for first-purchase conversion alone can attract low-LTV customers. Pairing CRO work with cohort-level CLV data ensures you're improving the quality of conversions, not just the quantity.
Predictive CLV
Predictive CLV uses historical purchase patterns, segment characteristics, and models (like Pareto/NBD or BG/NBD) to forecast future value before the relationship plays out. It's especially useful for early prioritization: which new customers are worth investing in for retention?