Freemium SaaS Unit Economics & Conversion Calculator
Simulate free user infrastructure burn, paid conversion rates, and blended customer lifetime profitability.
Parameters & Config
Average monthly subscription fee billed per active customer
Percentage of customers cancelling their subscription each month
Total sales and marketing expenditure required to acquire one customer
Percentage of subscription revenue retained after hosting and direct support costs
Total gross profit generated per customer over their active lifecycle
Benchmark metric for SaaS efficiency (Ideal: 3.0x to 5.0x)
Key Metrics & Sub-Totals
3 itemsCalculation Summary & Unit Breakdown
| Metric | Calculated Value | Notes / Logic |
|---|---|---|
| Monthly ARPU (Revenue/User) | $49.00 | Per user/month |
| Monthly Churn Rate | 4% | Customer attrition |
| Gross Margin Percentage | 70% | Cost of service deducted |
| Customer Lifespan | 25 months | 1 / Churn rate |
| Customer Acquisition Cost (CAC) | $180.00 | Blended marketing + sales |
| Customer Lifetime Value (LTV) | $857.50 | Total gross profit per customer |
| LTV to CAC Health Ratio | 4.76x | Benchmark: >3.0x |
| CAC Payback Period | 5.2 months | Benchmark: <12 months |
| Net LTV Profit Contribution | $677.50 | LTV minus CAC |
Overview & Methodology
Freemium models rely on free users converting to paid plans at a 2% to 5% rate. Free user infrastructure costs must be factored into the paid user’s gross margin to ensure overall business sustainability.
Mathematical Formulation
Paid LTV = (Paid ARPU × Blended Gross Margin) / Monthly Churn. Blended CAC = Marketing Spend / Total Converted Paid Users.Optimization Best Practices
Set strict usage limits (e.g. 3 projects, 1,000 records) on free tiers to trigger natural upgrade moments when users reach active value.
Monitor Free-to-Paid velocity: benchmark whether users convert within 14 days or take 90+ days.
If hosting costs for free users exceed 10% of total revenue, enforce 30-day inactivity purges.
Frequently Asked Questions
Q.What is a typical free-to-paid conversion rate for SaaS?
Self-serve freemium conversion benchmarks typically range between 2.0% and 4.5% across the software industry.
Q.How do free users impact paid gross margins?
Database, compute, and CDN costs for millions of non-paying users lower the effective gross margin of your paying user cohort.
Q.What is the LTV on a $49 plan with 4% churn and 70% blended margin?
Monthly gross profit is $34.30. Divided by 0.04 churn, LTV is $857.50.