Free tool · 2026
LTV : CAC Ratio Calculator
The single most-cited efficiency metric in SaaS. Healthy businesses sit at 3:1 or better; below 1:1 is losing money on every customer. This calculator shows you which side you're on — and how many months until you've earned back what you spent.
Your numbers
Update any field — results recalculate as you type.
Total expected revenue or profit per customer over their lifetime
Total fully-loaded acquisition cost per customer
Applied only when LTV is in revenue terms
Used to compute CAC payback period in months
LTV : CAC Ratio
How the math works
LTV : CAC Ratio
LTV:CAC = Gross-Profit LTV ÷ CACUse gross-profit LTV, not revenue LTV. CAC is paid in real cash; revenue without COGS-adjustment inflates the ratio. 3:1 is healthy for SaaS; 1.5:1 acceptable for ecommerce; below 1:1 is losing money.
CAC Payback Period
Payback (months) = CAC ÷ Monthly Gross Profit per CustomerLTV:CAC tells you if your business is sustainable; payback tells you when cash arrives. A 5:1 business with 36-month payback is structurally healthy but cash-hungry. Target 6–18 months for B2B SaaS, 3–6 for consumer subscription, 1–3 for ecommerce.
Want to go deeper? Read the LTV:CAC glossary entry for the full definition, or pair this tool with the ROAS calculator to model the campaign-level math feeding into your acquisition cost.
Frequently asked
›What is a healthy LTV:CAC ratio?
Industry consensus for SaaS: 3:1 or better indicates sustainable growth. Below 1:1 means you're losing money on each customer. Above 5:1 sometimes signals underinvestment in growth — you could spend more on acquisition without breaking the model. For ecommerce, 1.5:1 to 2:1 can be sustainable because payback is faster.
›Should I use revenue LTV or profit LTV in the calculation?
Gross-profit LTV, almost always. CAC is paid in real cash. Comparing it to revenue LTV (without COGS) inflates the ratio. The honest comparison is dollars of margin per dollar of acquisition cost.
›What's a good CAC payback period?
Depends on business model. B2B SaaS: 6–18 months for sustainable growth, 24+ months tolerable for venture-backed scale-ups with strong LTV. Consumer subscription: 3–6 months. Ecommerce: 1–3 months. Longer payback isn't bad if LTV:CAC is strong — it just means you're cash-hungry.
›How is LTV:CAC different from ROAS?
ROAS is a campaign-level efficiency metric (revenue ÷ ad spend for one campaign or channel). LTV:CAC is a business-level unit-economics metric covering the customer's full lifetime. ROAS is what you optimize daily; LTV:CAC is what determines whether the business is sustainable.
›How often should LTV:CAC be calculated?
Monthly at the cohort level (channel × acquisition month) for tactical decisions; quarterly at the company level for board reporting. Watch for cohort-level drift — your company-level LTV:CAC can look healthy while a new acquisition channel quietly runs at 1:1.
Track LTV:CAC by channel, not just at the company level.
Floowzy joins Stripe revenue with acquisition channel data and tracks LTV-adjusted ROAS per channel — so you see which channels are quietly running at 1:1 while your company-level number stays healthy.