LTV:CAC Ratio Calculator
Calculate customer lifetime value, acquisition cost, and the LTV:CAC ratio for your SaaS or subscription business. Instantly assess unit economics health.
LTV Inputs
Monthly revenue per customer, before costs.
Percentage of revenue after direct costs (COGS). SaaS typical: 70-85%.
Percentage of customers who cancel each month.
CAC Inputs
Total monthly spend on sales and marketing (salaries, ads, tools, events).
Number of new paying customers acquired in the same period.
Quick Tips
- Include fully-loaded S&M costs (salaries, tools, ads) for accurate CAC.
- Use gross margin LTV, not revenue LTV, for realistic unit economics.
- Track LTV:CAC monthly and watch the trend, not just the snapshot.
Your LTV:CAC Ratio
Customer LTV
$1,600
CAC
$500
Strong unit economics. Your business generates solid returns on customer acquisition investment.
Detailed Breakdown
Important Note
This calculator uses a simplified LTV model assuming constant ARPU and churn. Real-world LTV may differ due to expansion revenue, non-linear churn curves, and discount rates. Use these results as directional guidance alongside your financial models.
What Is the LTV:CAC Ratio?
The LTV:CAC ratio is the single most important unit economics metric for SaaS and subscription businesses. It compares the total revenue a customer generates over their entire relationship with your company (Customer Lifetime Value, or LTV) against the cost of acquiring that customer (Customer Acquisition Cost, or CAC). This ratio tells you whether your business model is fundamentally profitable at the individual customer level, which is the foundation of sustainable growth.
Investors, board members, and SaaS operators all rely on the LTV:CAC ratio to evaluate business health. A company with a strong ratio can confidently invest in growth, knowing that each new customer will generate a meaningful return. A company with a weak ratio faces a cash trap: the more customers it acquires, the more money it loses. Understanding and optimizing this metric is essential for any recurring revenue business, from early-stage startups to public companies. The benchmark of 3:1 was popularized by venture capitalist David Skok and has become the industry standard for healthy SaaS economics.
How to Calculate the LTV:CAC Ratio
The LTV:CAC ratio requires two components: Customer Lifetime Value and Customer Acquisition Cost. Here is how to compute each one step by step.
LTV Formula
LTV = ARPU x Gross Margin % / Monthly Churn Rate
ARPU — Average Revenue Per User per month (total MRR / total customers)
Gross Margin % — Revenue minus Cost of Goods Sold, as a decimal (e.g., 0.80 for 80%)
Monthly Churn Rate — Percentage of customers lost per month, as a decimal (e.g., 0.05 for 5%)
CAC Formula
CAC = Total Sales & Marketing Spend / New Customers Acquired
Total S&M Spend — All sales and marketing costs in the period (salaries, ads, tools, events, overhead)
New Customers — Number of net-new paying customers acquired in the same period
Ratio & Payback
LTV:CAC Ratio = LTV / CAC
Payback Period = CAC / (ARPU x Gross Margin)
First, calculate your ARPU by dividing your Monthly Recurring Revenue by your total number of active customers. Then determine your gross margin by subtracting direct costs such as hosting, support, and payment processing from revenue. Divide the gross-margin-adjusted ARPU by your monthly churn rate to get LTV. For CAC, sum every dollar your sales and marketing teams spend, including fully-loaded salaries, and divide by the number of new customers signed in that same period. Finally, divide LTV by CAC for the ratio, and divide CAC by monthly gross profit per customer for the payback period in months.
Worked Examples
These real-world scenarios illustrate how different SaaS business profiles produce different LTV:CAC outcomes.
Example 1: Early-Stage B2B SaaS
ARPU = $80/mo, Gross Margin = 75%, Monthly Churn = 6%, S&M Spend = $30,000/mo, New Customers = 40
LTV = $80 x 0.75 / 0.06 = $1,000
CAC = $30,000 / 40 = $750
LTV:CAC = $1,000 / $750 = 1.3:1 (Inefficient — needs improvement)
Payback = $750 / ($80 x 0.75) = 12.5 months
Example 2: Mature Mid-Market SaaS
ARPU = $200/mo, Gross Margin = 82%, Monthly Churn = 2.5%, S&M Spend = $100,000/mo, New Customers = 60
LTV = $200 x 0.82 / 0.025 = $6,560
CAC = $100,000 / 60 = $1,667
LTV:CAC = $6,560 / $1,667 = 3.9:1 (Healthy)
Payback = $1,667 / ($200 x 0.82) = 10.2 months
Example 3: Enterprise SaaS with Low Churn
ARPU = $500/mo, Gross Margin = 85%, Monthly Churn = 1%, CAC = $5,000 (known)
LTV = $500 x 0.85 / 0.01 = $42,500
LTV:CAC = $42,500 / $5,000 = 8.5:1 (Under-investing in growth)
Payback = $5,000 / ($500 x 0.85) = 11.8 months
LTV:CAC Benchmark Table
Use this table to benchmark your ratio against industry standards and understand what each range means for your business.
| LTV:CAC Ratio | Rating | Meaning | Action |
|---|---|---|---|
| < 1:1 | Unsustainable | Losing money on every customer | Cut CAC or pivot pricing/retention urgently |
| 1:1 - 2:1 | Inefficient | Marginal economics, limited growth runway | Reduce churn, increase ARPU, optimize channels |
| 3:1 - 5:1 | Healthy | Strong unit economics, sustainable growth | Maintain and scale acquisition efforts |
| > 5:1 | Under-investing | Leaving growth on the table | Increase S&M spend to capture more market |
When to Use This Calculator
The LTV:CAC ratio calculator is essential in several key business situations where understanding unit economics drives important decisions.
- Fundraising and investor meetings: Investors expect to see LTV:CAC as part of your SaaS metrics deck. A ratio of 3:1 or better signals a fundable business model with efficient customer acquisition and strong retention.
- Budget planning: When deciding how much to allocate to sales and marketing next quarter, the LTV:CAC ratio tells you whether you can afford to spend more or need to pull back. It directly informs your growth budget.
- Pricing changes: Before and after adjusting your pricing, recalculate the ratio to understand how price changes affect unit economics. Higher ARPU improves LTV, but watch for churn impact.
- Channel evaluation: Calculate LTV:CAC per acquisition channel (paid ads, content marketing, outbound sales) to identify which channels deliver the best return and deserve more investment.
- Board reporting: Include the LTV:CAC ratio and its trend over time in monthly or quarterly board updates. It is one of the most closely watched SaaS metrics alongside MRR growth and net retention.
Tips for Accurate Results
Getting accurate LTV:CAC numbers requires careful input selection. These best practices help you avoid the most common mistakes.
- Use fully-loaded CAC. Include all sales and marketing costs: salaries, commissions, ad spend, tools, event sponsorships, and departmental overhead. Under-counting CAC creates a falsely optimistic ratio.
- Always use gross margin LTV. Revenue-based LTV overstates customer value. Multiply ARPU by gross margin first to reflect the actual economic contribution of each customer after direct costs.
- Match your time periods. If your S&M spend is from Q1, your new customer count should also be from Q1. Mixing periods produces misleading CAC numbers, especially in businesses with long sales cycles.
- Segment by cohort. Enterprise customers and SMB customers often have very different LTV:CAC profiles. Blending them together can mask problems in one segment. Calculate the ratio separately for each customer segment.
- Account for expansion revenue. This calculator uses a simplified LTV model. If your business has significant upsell and cross-sell revenue, your actual LTV may be higher. Consider adding net revenue retention to your analysis.
Frequently Asked Questions
About This Calculator
Free LTV:CAC ratio calculator for SaaS and subscription businesses. Compute customer lifetime value, acquisition cost, and payback period now.
Frequently Asked Questions
How do I use the Ltv Cac Ratio Calculator?
Enter your values in the input fields provided, and the calculator will automatically compute results in real-time. Start with the required fields (marked with labels), then adjust optional parameters to fine-tune your calculation. Results update instantly as you change inputs, allowing you to quickly compare different scenarios. For the most accurate results, use precise figures from official documents rather than rough estimates. If you are unsure about any input, hover over the field label for a brief explanation of what value to enter.
How accurate are the results from the Ltv Cac Ratio Calculator?
This calculator uses standard industry formulas and up-to-date 2025 data to provide reliable estimates. Results are most accurate when you input precise, verified figures. Keep in mind that calculators provide estimates based on mathematical models — real-world outcomes may vary due to factors not captured in the inputs, such as market changes, policy updates, or individual circumstances. For high-stakes decisions, use these results as a starting point and consult with a relevant professional (financial advisor, doctor, engineer, etc.) for personalized guidance.
Can I save or share my Ltv Cac Ratio Calculator results?
You can bookmark this page or take a screenshot of your results for future reference. To share results with others, copy the page URL — your specific inputs are not stored in the URL for privacy reasons, so the recipient will need to enter their own values. For record-keeping purposes, we recommend noting your inputs and results in a spreadsheet or document. This allows you to track changes over time and compare different scenarios side by side.
What formulas does the Ltv Cac Ratio Calculator use?
This calculator uses industry-standard formulas that are widely accepted by professionals in this field. The specific mathematical relationships and constants are based on peer-reviewed research, government guidelines, or established industry practices. Where applicable, we reference the source methodology in the educational content below the calculator. If you need to verify a specific formula for professional or academic purposes, the calculation methodology section provides detailed breakdowns of each step.
Is the Ltv Cac Ratio Calculator free to use?
Yes, this calculator is completely free with no registration required. We believe financial and analytical tools should be accessible to everyone. There are no hidden fees, premium features locked behind paywalls, or data collection requirements. You can use the calculator as many times as needed, compare unlimited scenarios, and access all features without creating an account. The tool runs entirely in your browser — your inputs are never sent to our servers or stored anywhere.