Last updated: May 2026
Quick Answer
LTV = Average Order Value × Purchase Frequency × Customer Lifespan. The 3:1 LTV:CAC ratio is the benchmark for sustainable growth — you make $3 in lifetime value for every $1 spent acquiring a customer. Always calculate profit LTV (not revenue LTV) when comparing against CAC.
Key Takeaways
- ✓ Use profit LTV vs CAC: Revenue LTV overstates what you can spend — gross margin LTV is the correct numerator.
- ✓ The 3:1 benchmark: LTV:CAC of 3:1+ means healthy growth. Below 1:1 means you're destroying value at scale.
- ✓ Churn is the biggest lever: Cutting churn in half roughly doubles LTV — often more impactful than increasing AOV.
- ✓ LTV unlocks ad budgets: A business with $1,200 LTV can spend 4× more on acquisition than one with $300 LTV and still profit.
How to Use This Calculator (With Example)
Enter your Average Order Value, how many times a customer buys per year, and how many years they typically stay. Optionally add your gross margin to see profit LTV, and your CAC to calculate the ratio.
Scenario: "FitBox" — Monthly Fitness Subscription
- Monthly plan price (AOV): $49
- Purchase frequency: 12 (monthly billing = 12x/year)
- Average customer lifespan: 2.5 years (40% annual churn = 1/0.4)
- Gross margin: 55%
- CAC: $210 (Meta + Google ads combined)
The Results
Annual Value: $49 × 12 = $588/year
Lifetime Revenue: $588 × 2.5 = $1,470
Lifetime Profit: $1,470 × 55% = $808.50
LTV:CAC Ratio: $808.50 ÷ $210 = 3.85:1 — Healthy ✓
FitBox earns $3.85 in gross profit for every $1 spent on acquisition. They can confidently increase ad spend. If they reduce churn to 30% (lifespan = 3.33 years), LTV:CAC rises to 5.1:1 — a signal to invest even more aggressively.
LTV for SaaS vs. eCommerce — Key Differences
SaaS / Subscription businesses have highly predictable LTV because revenue recurs until cancellation. Churn rate is the dominant variable — a 1% reduction in monthly churn can increase LTV by 10–15%. The standard formula is often simplified to: LTV = ARPU ÷ Churn Rate (monthly).
eCommerce businesses have more variable LTV because purchase timing and frequency fluctuate. RFM analysis (Recency, Frequency, Monetary value) is often layered on top of simple LTV to predict which customers are most likely to buy again. LTV also varies dramatically by acquisition channel — organic SEO customers may have 3× the LTV of paid traffic customers.
Why Profit LTV — Not Revenue LTV — Matters
This is the most common LTV mistake. Consider two businesses:
- Business A: LTV = $1,000, gross margin = 20% → Profit LTV = $200. Max sustainable CAC ≈ $67 (at 3:1).
- Business B: LTV = $600, gross margin = 60% → Profit LTV = $360. Max sustainable CAC ≈ $120 (at 3:1).
Business B appears to have the lower LTV — but it can actually afford to spend nearly twice as much on customer acquisition. Revenue LTV is a vanity metric; profit LTV is what drives real decisions.
How to Improve LTV: The Three Levers
- Increase Average Order Value: Upsell to higher-tier plans, bundle products, introduce complementary add-ons, or remove the cheapest entry tier. A 20% AOV increase produces a 20% LTV increase with no churn impact.
- Increase Purchase Frequency: Email re-engagement, win-back campaigns, loyalty and rewards programs, subscription upsells. For eCommerce, personalized product recommendations significantly lift repeat purchase rates.
- Reduce Churn (most powerful lever): Improve onboarding so customers achieve their first success quickly. Add proactive check-ins at 30/60/90 days. Offer annual plans at a discount (annual subscribers churn 4–5× less than monthly). Detect at-risk customers early using usage data and intervene.
Frequently Asked Questions
What is Customer Lifetime Value (LTV)?
Customer Lifetime Value (LTV or CLV) is the total expected revenue — or profit — a business will generate from a single customer throughout their entire relationship. It's the single most important number for setting sustainable marketing budgets.
Why is LTV important?
LTV dictates how much you can afford to spend to acquire a new customer. If your LTV is $600 and your CAC is $200, you have a 3:1 ratio — the standard benchmark for sustainable growth. A business with a higher LTV than competitors can outspend them on ads and still remain profitable.
What is a good LTV:CAC ratio?
3:1 is the standard SaaS benchmark for sustainable scaling. Below 1:1 means you're losing money on every customer. Above 5:1 often means you're under-investing in growth — you could safely acquire more customers. Most VCs consider 3:1 the floor for fundable businesses.
How do I increase my LTV?
The three primary levers are: (1) Increase Average Order Value via upsells, bundles, or price increases. (2) Increase Purchase Frequency via loyalty programs, subscriptions, or re-engagement campaigns. (3) Reduce Churn — keeping customers longer has a compounding effect on LTV.
Should I use revenue LTV or profit LTV?
Always use profit LTV (gross margin LTV) when comparing against CAC. Revenue LTV overstates what you can afford to spend — you don't keep all revenue. If your gross margin is 40%, then $1,000 in revenue LTV is really only $400 in profit LTV to compare against CAC.
What is the difference between LTV and predicted LTV?
Simple LTV (what this calculator computes) uses historical averages: AOV × Frequency × Lifespan. Predictive LTV uses machine learning on individual customer behaviour patterns to forecast future purchases per customer. Simple LTV is sufficient for most strategic decisions; predictive LTV is used by large retailers and SaaS companies with rich data.