Break-Even Cohort Retention Analyzer
Calculate when customer cohorts become profitable and analyze LTV:CAC ratio. Enter values for instant results with step-by-step formulas.
Worked Examples
Example 1: SaaS Startup Analysis
Problem: SaaS startup: $200 CAC, $30/mo ARPU, 80% gross margin, 6% monthly churn. Analyzing 1,000-customer cohort. When do they break even?
Solution: Cohort Parameters:\nCohort size: 1,000 customers\nCAC per customer: $200\nTotal acquisition cost: $200,000\nMonthly ARPU: $30\nGross margin: 80%\nMargin per customer-month: $30 Γ 80% = $24\nMonthly churn: 6%\n\nMonth-by-Month Analysis:\n\nMonth 0:\nCustomers: 1,000\nRevenue: $0 (just acquired)\nMargin: $0\nCost: $200,000\n\nMonth 1:\nRetained: 1,000 Γ (1-0.06) = 940\nRevenue: 1,000 Γ $30 = $30,000\nMargin: $24,000\nCumulative margin: $24,000\nProfit: -$176,000\n\nMonth 2:\nRetained: 940 Γ 0.94 = 884\nMargin this month: $21,216\nCumulative: $45,216\nProfit: -$154,784\n\nContinuing...\n\nMonth 6:\nRetained: 1,000 Γ (0.94)^6 = 689\nCumulative margin: ~$120,000\nProfit: -$80,000\n\nMonth 9:\nRetained: 1,000 Γ (0.94)^9 = 572\nCumulative margin: ~$165,000\nProfit: -$35,000\n\nMonth 10:\nRetained
Result: Break-even: Month 10 | LTV:CAC 2.15:1 (Fair) | 47.5% retained at year 1 | Improve retention
Example 2: High-Churn Mobile App
Problem: Consumer app: $5 CAC, $10/mo subscription, 90% margin, but 12% monthly churn. Is this viable?
Solution: Unit Economics:\nCAC: $5\nARPU: $10/month\nMargin per month: $10 Γ 90% = $9\nMonthly churn: 12%\n\nQuick Check:\nBreak-even requires: $5 CAC / $9 margin = 0.56 months\nSo break-even is instant (first month)\n\nBut what's LTV?\n\nMonth-by-Month:\nMonth 1: 100% remain, earn $9 margin\nMonth 2: 88% remain, earn $7.92\nMonth 3: 77.4% remain, earn $6.97\n...\n\nCumulative LTV Formula:\nLTV = Margin / Churn Rate\nLTV = $9 / 0.12 = $75\n\nLTV:CAC = $75 / $5 = 15:1\n\nWow! Excellent ratio!\n\nBUT: 12% monthly churn is very high\nRetention:\nMonth 3: 77%\nMonth 6: 47%\nMonth 12: 22% (only 1 in 5 remain!)\n\nIs this sustainable?\n\nPros:\n- Instant break-even\n- 15:1 LTV:CAC is amazing\n- Low CAC enables aggressive scaling\n\nCons:\n- Weak product-market fit (12% churn)\n- Constant churn treadmill\n
Result: Instant break-even | 15:1 LTV:CAC (Excellent) | BUT 12% churn is fragile | Fix retention
Example 3: Annual Contract Cohort
Problem: B2B SaaS with annual contracts. $5K CAC, $500/mo ($6K annual), 70% margin, 20% annual churn. Analyze 100-customer cohort.
Solution: Annual Contract Mechanics:\nCAC: $5,000\nARR per customer: $6,000\nGross margin: 70%\nMargin per customer-year: $6,000 Γ 70% = $4,200\nAnnual churn: 20%\n\nConvert to monthly for analysis:\nMonthly churn β 20% / 12 β 1.8%\n(This is approximation; actual is geometric)\n\nCohort: 100 customers\nTotal CAC: $500,000\n\nYear-by-Year:\n\nYear 0 (acquisition):\nCustomers: 100\nRevenue: $0 (just signed)\nMargin: $0\nCost: $500,000\nProfit: -$500,000\n\nYear 1:\nRevenue recognized: 100 Γ $6,000 = $600,000\nMargin: $420,000\nCumulative margin: $420,000\nProfit: -$80,000 (not yet break-even)\n\nYear 2:\nRetained: 100 Γ 80% = 80\nRevenue: 80 Γ $6,000 = $480,000\nMargin: $336,000\nCumulative: $756,000\nProfit: $256,000 (broke even during year 2!)\n\nActual Break-even:\n$500K CAC / $420K margin/year = 1
Result: Break-even: 14-15 months | LTV:CAC 2.05:1 | $10.2K LTV | Healthy B2B metrics
Frequently Asked Questions
What is cohort retention analysis?
Cohort retention tracks a group of customers acquired in the same period to see how many remain active over time. It reveals product stickiness, churn patterns, and long-term value. Essential for subscription businesses and marketplaces.
How do I calculate break-even month?
Break-even month is when cumulative gross margin from a cohort equals the total customer acquisition cost for that cohort. It's the point where you've recovered your marketing spend and start generating profit.
What's the difference between gross and net retention?
Gross retention is percentage of customers who remain (churn losses only). Net retention includes expansion revenueβif remaining customers grow spending, NRR can exceed 100%. Gross measures stickiness; net measures growth efficiency.
How long should it take to break even on CAC?
SaaS benchmarks: 12-18 months is healthy. Under 12 months is excellent (suggests you could spend more on acquisition). Over 24 months is concerning (long payback period increases capital requirements and risk).
How does cohort analysis differ from aggregated metrics?
Aggregated metrics (overall churn, overall ARPU) hide cohort performance variations. January cohort might retain better than July cohort. Cohort analysis reveals these patterns, showing impact of product changes or seasonal factors.
How do I calculate break-even point?
Break-even point is where total revenue equals total costs. In units: BEP = Fixed Costs / (Price per Unit - Variable Cost per Unit). In revenue: BEP = Fixed Costs / Contribution Margin Ratio. For example, with 50,000 dollars in fixed costs, a 100 dollar price, and 60 dollar variable cost, BEP = 1,250 units or 125,000 dollars in revenue.