Customer Lifetime Value (CLV) Simulator
Stress-test customer lifetime value against changes in churn, margin, and retention assumptions.
Formula
Simple LTV = (ARPU × Gross Margin) / Monthly Churn; LTV:CAC Ratio = LTV / CAC; Payback Months = CAC / (ARPU × Gross Margin)
The simple LTV formula divides monthly contribution margin by churn rate. Monthly contribution (ARPU × Margin) represents profit per customer per month. Dividing by churn converts this to total expected profit—if churn is 5%, the customer stays on average 20 months (1/0.05), earning 20 × contribution. LTV:CAC compares lifetime profit to acquisition cost; 3:1+ is healthy. Payback calculates months to recover CAC. The formula works because it translates periodic unit economics into lifetime value through the lens of retention duration, enabling comparison of customer economics across different business models.
Worked Examples
Example 1: SaaS Unit Economics Analysis
Problem:A B2B SaaS company has: $200 ARPU, 75% gross margin, 3% monthly churn, $600 CAC, and 5% monthly expansion. Calculate LTV, LTV:CAC, payback, and net retention.
Solution:Step 1: Calculate Simple LTV LTV = (ARPU × Margin) / Churn LTV = ($200 × 0.75) / 0.03 LTV = $150 / 0.03 = $5,000 Step 2: Account for Expansion Net Churn = Gross Churn - Expansion = 3% - 5% = -2% Negative net churn means cohorts grow! Adjusted LTV using 60-month cap: ~$9,000+ Step 3: Calculate LTV:CAC LTV:CAC = $5,000 / $600 = 8.3:1 With expansion: ~15:1 ✓ Excellent Step 4: Calculate Payback Monthly Contribution = $200 × 0.75 = $150 Payback = $600 / $150 = 4 months ✓ Excellent Step 5: Net Revenue Retention NRR = (1 - 0.03 + 0.05)^12 = 1.02^12 = 127% Conclusion: Outstanding unit economics with negative net churn.
Result:$5,000+ LTV | 8.3:1 LTV:CAC | 4-month payback | 127% NRR | Excellent metrics
Example 2: E-commerce Subscription Box
Problem:Subscription box: $35 ARPU, 40% gross margin, 8% monthly churn, $45 CAC. Is this business viable? What improvements are needed?
Solution:Current State Analysis: LTV = ($35 × 0.40) / 0.08 LTV = $14 / 0.08 = $175 LTV:CAC = $175 / $45 = 3.9:1 ✓ Acceptable Payback = $45 / $14 = 3.2 months ✓ Good Average Lifetime = 1 / 0.08 = 12.5 months Assessment: Viable but thin margins. High churn limits LTV. Improvement Scenarios: 1. Reduce churn to 5%: LTV = $14 / 0.05 = $280 LTV:CAC = 6.2:1 (+59% improvement) 2. Increase ARPU to $45 (premium tier): LTV = ($45 × 0.40) / 0.08 = $225 LTV:CAC = 5.0:1 (+28% improvement) 3. Improve margin to 50% (better sourcing): LTV = ($35 × 0.50) / 0.08 = $219 LTV:CAC = 4.9:1 (+26% improvement) Recommendation: Focus on churn reduction first—highest leverage.
Result:$175 LTV | 3.9:1 LTV:CAC viable | Churn reduction to 5% adds $105 LTV (+60%)
Example 3: Comparing Customer Segments
Problem:A software company has two segments: SMB ($50 ARPU, 7% churn, $100 CAC) and Enterprise ($500 ARPU, 2% churn, $2,000 CAC). Both at 80% margin. Which segment deserves more investment?
Solution:SMB Segment: LTV = ($50 × 0.80) / 0.07 = $571 LTV:CAC = $571 / $100 = 5.7:1 Payback = $100 / $40 = 2.5 months Avg Lifetime = 14 months Enterprise Segment: LTV = ($500 × 0.80) / 0.02 = $20,000 LTV:CAC = $20,000 / $2,000 = 10:1 Payback = $2,000 / $400 = 5 months Avg Lifetime = 50 months Comparison: - Enterprise LTV is 35x higher ($20K vs $571) - Enterprise LTV:CAC is 1.75x better (10:1 vs 5.7:1) - Enterprise payback is 2x longer but still healthy - Enterprise lifetime is 3.5x longer Unit Economics Winner: Enterprise But consider: - Enterprise sales cycle is longer - SMB is self-serve, more scalable - Enterprise concentration risk Recommendation: Enterprise for profitability, SMB for scalable growth. Optimal: Land SMB, expand to Enterprise.
Result:Enterprise: $20K LTV, 10:1 ratio | SMB: $571 LTV, 5.7:1 ratio | Enterprise wins on economics, SMB on scalability
Frequently Asked Questions
What is Customer Lifetime Value (CLV/LTV)?
CLV is the total profit a customer generates over their entire relationship with your business. It combines average revenue, profit margin, and customer lifespan. Understanding CLV helps determine how much to invest in acquisition and retention.
How does churn rate impact LTV?
Churn has exponential impact on LTV. At 5% monthly churn, average lifetime is 20 months. At 3%, it's 33 months—65% longer. Small churn improvements dramatically increase LTV. This is why retention is often more valuable than acquisition.
What is net revenue retention (NRR)?
NRR = (Starting MRR + Expansion - Contraction - Churn) / Starting MRR. NRR above 100% means cohorts grow in value over time, even accounting for churn. Best SaaS companies achieve 120%+ NRR through upsells and cross-sells.
Should I use DCF for LTV calculations?
Discounted Cash Flow (DCF) LTV accounts for time value of money—a dollar today is worth more than a dollar in 3 years. For long customer lifetimes or high discount rates, DCF LTV is significantly lower than simple LTV. Use it for accurate financial planning.
How do I improve LTV?
Three levers: increase ARPU (upsells, price increases), improve retention (reduce churn through better product/service), and drive expansion (cross-sells, usage growth). Retention usually has the highest ROI because it compounds over the customer lifetime.
What's a reasonable payback period?
12 months or less is healthy for most businesses. Under 6 months is excellent. Over 18 months is risky—you're financing customer acquisition for too long. SaaS companies often tolerate longer payback if retention is strong.
How do I segment LTV analysis?
Calculate LTV by acquisition channel, customer segment, pricing tier, and cohort. You'll find some segments are 5-10x more valuable than others. Focus acquisition on high-LTV segments and consider whether low-LTV segments are worth serving.
What are LTV calculation pitfalls?
Common mistakes: using revenue instead of margin, ignoring variable costs, assuming constant churn over lifetime, not segmenting, forgetting expansion revenue, and using too-short observation windows. Always validate LTV models against actual cohort data.
How is customer lifetime value (CLV) calculated?
Simple CLV = Average Purchase Value * Purchase Frequency * Customer Lifespan. For subscription models: CLV = Average Monthly Revenue per Customer / Monthly Churn Rate. For example, if a customer pays 50 dollars/month and your monthly churn is 5%, CLV = 50/0.05 = 1,000 dollars. CLV should be at least 3 times your customer acquisition cost.
How do I calculate customer acquisition cost (CAC)?
CAC = Total Sales and Marketing Expenses / Number of New Customers Acquired in that period. Include all related costs: advertising, salaries, tools, commissions, and overhead. CAC payback period = CAC / Monthly Gross Margin per Customer. A payback period under 12 months is generally healthy for SaaS businesses.