CAC, LTV & Payback Calculator

Is your unit economics actually working?

Enter your SaaS unit economics to see lifetime value, CAC payback period, and whether your LTV:CAC ratio meets industry benchmarks. The margin-adjusted LTV formula used here is the standard one investors and operators reference: (ARPU × gross margin) / monthly churn.

Revenue

$/mo
%

Revenue left after delivery costs (hosting, support, payment fees).

Retention

%

Share of customers you lose each month. 2% is a strong SaaS benchmark.

Acquisition

$

All-in cost to acquire one customer: ad spend, sales salaries, tooling.

Advanced

%

Optional. Discounts future cash flows for NPV-adjusted LTV. Leave at 0 for the simple formula.

LTV (margin-adj.)
$2,000

Without margin: $2,667

LTV : CAC ratio
5.0 : 1

Healthy SaaS targets 3:1 or better.

CAC payback period
6.7 mo
Best-in-class (< 12 mo)
Avg customer lifetime
33.3 mo

26.7 mo profitable after payback

Verdict

Healthy — solid SaaS unit economics.

Each customer pays back acquisition cost several times over. You can reinvest the surplus into growth with confidence.

Sensitivity: LTV:CAC vs monthly churn

Current: 3.0% → 5.0:1

Churn is the single biggest lever on LTV. A 1-point reduction can swing your ratio dramatically.

0:11:13:15:115:1healthy 3:11%3%5%8%10%12%15%monthly churn rate

What if?

How LTV:CAC and payback shift as you raise ARPU or cut CAC. Holding churn and margin constant.

ARPU scenarioCAC scenarioLTV:CACPayback
Current ARPUCurrent CAC5.0 : 16.7 mo
+10% ARPU−20% CAC6.9 : 14.8 mo
+25% ARPU−40% CAC10.4 : 13.2 mo

SaaS benchmarks

Compiled from Bessemer Venture Partners' State of the Cloud and OpenView / SaaS Capital public benchmark reports.

  • LTV:CAC ratio
    > 3 : 1
    Healthy SaaS
  • CAC payback
    < 12 months
    Best-in-class
  • Monthly churn
    < 2%
    Healthy SMB / mid-market SaaS
  • Gross margin
    > 70%
    Pure-software SaaS

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