LTV:CAC Ratio Calculator
(Growth Efficiency Tool)
This free calculator checks your LTV:CAC ratio against the widely cited 3:1 benchmark. Don't know your LTV? Build one from monthly revenue, margin, and customer lifespan.
Step 1 — Calculation Goal
Step 2 — Core Metrics
Total revenue expected from one customer over their lifetime
Fully loaded cost to acquire one customer
LTV:CAC Ratio Result
💡 Formula Guide
Related Calculators
What Is the LTV:CAC Ratio?
The LTV:CAC ratio compares how much revenue a customer generates over their entire relationship with your business (LTV) to how much it cost to acquire them (CAC). It is the standard way subscription businesses and investors judge whether acquisition spend is actually building a sustainable business, rather than just buying growth at a loss.
Example
A customer with a lifetime value of $900 and a CAC of $200 gives a ratio of $900 ÷ $200 = 4.5:1 — meaning the customer is worth 4.5 times what it cost to acquire them.
The 3:1 Benchmark — Where It Comes From and What It Means
A 3:1 LTV:CAC ratio is repeatedly cited across SaaS metrics literature and venture-capital growth-efficiency frameworks as a marker of healthy, capital-efficient growth. It isn't a law of business — it's a heuristic that balances two failure modes: spending too much to acquire customers (ratio near or below 1:1), and spending too little, leaving growth on the table (ratio well above 5:1).
| LTV:CAC Ratio | What It Generally Signals |
|---|---|
| Below 1:1 | Losing money on every customer acquired |
| 1:1 – 3:1 | Marginally profitable; little buffer for rising costs or churn |
| 3:1 – 5:1 | Widely cited as efficient, scalable range |
| Above 5:1 | Can signal underinvestment in growth relative to customer value |
Treat the benchmark as directional. Early-stage, well-capitalized companies sometimes deliberately run a lower ratio to grow faster; cash-constrained businesses need a higher one to stay solvent. Compare your ratio over time and against companies at a similar stage, not against 3:1 in isolation.
Estimating LTV When You Don't Know It Exactly
A simplified LTV model multiplies average monthly revenue per customer by gross margin and average customer lifespan in months.
Example: $75 average monthly revenue, 80% gross margin, and a 24-month average customer lifespan gives an estimated LTV of $75 × 0.80 × 24 = $1,440. This simplified model is useful for a quick sanity check; more rigorous LTV models incorporate cohort-based retention curves and discount rates for revenue received further in the future, which this calculator does not attempt to replicate.
How to Use This Free LTV:CAC Calculator
- LTV:CAC Ratio: Enter LTV and CAC to check your current efficiency against the benchmark.
- Required LTV: Enter a target ratio and your CAC to see what customer value you need to hit it.
- Max Sustainable CAC: Enter LTV and a target ratio to find the highest CAC you can afford while staying within that ratio.
💡 Pro Tip: Pair this with the CAC Calculator to get your CAC and payback period first, then plug it in here to check overall growth efficiency.
Frequently Asked Questions About LTV:CAC
What does LTV:CAC ratio measure?
It compares Customer Lifetime Value to Customer Acquisition Cost as a ratio, showing whether acquisition spend is generating sustainable returns. Formula: LTV ÷ CAC.
What is a good LTV:CAC ratio?
3:1 is the most commonly cited healthy benchmark. Below 1:1 means losing money per customer; above 5:1 can mean underinvesting in growth. Treat these as directional guidelines, not fixed rules.
How do I estimate LTV without exact data?
Use Avg. Monthly Revenue per Customer × Gross Margin % × Avg. Customer Lifespan in months. This calculator's LTV builder does this automatically when you don't have a precise LTV figure.
Does a higher ratio always mean better performance?
Not necessarily — a ratio well above 5:1 can mean a company is spending too conservatively on acquisition and could grow faster by investing more, as long as efficiency holds at the margin.
How is this different from CAC payback period?
LTV:CAC measures total lifetime return versus acquisition cost as a ratio. CAC payback period measures how many months it takes to recover the acquisition cost from revenue. They're usually tracked together, not as substitutes for each other.
Last Updated: September 2026 | Benchmarks reflect commonly cited ranges from SaaS metrics literature and venture-capital growth-efficiency reporting.