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SaaS Metrics Calculator

Calculate MRR, ARR, LTV, CAC payback, and LTV:CAC in one place.

Updated June 2026 · Editorial standards

SaaS inputs

$
%
$
MRR
$25,000
ARR
$300,000
Customer LTV
$1,667
LTV : CAC ratio
5.6:1

You have $25,000 MRR ($300,000 ARR). Each customer's LTV is $1,667 against $300 CAC — a 5.6:1 ratio.CAC payback: 6 months. A LTV:CAC of 3:1+ and payback under 12 months are common SaaS benchmarks. Your unit economics look healthy.

By the KalkWise Editorial Team Reviewed for accuracy Updated June 2026

What is the saas metrics calculator?

In short

Core SaaS metrics flow from customers, ARPU, and churn. With 500 customers at $50 ARPU, MRR is $25,000 and ARR is $300,000. At 3% monthly churn the average customer lasts ~33 months, giving an LTV of about $1,650 — compare it to CAC for a healthy 3:1 LTV:CAC ratio.

Calculates key SaaS metrics — MRR, ARR, customer LTV, CAC payback period, and LTV:CAC ratio — from your customer count, ARPU, churn, and acquisition cost.

How to use this calculator

  1. 1Enter your number of active customers and monthly ARPU.
  2. 2Enter your monthly churn rate (average lifespan ≈ 1 / churn).
  3. 3Enter your customer acquisition cost.
  4. 4See MRR, ARR, LTV, CAC payback, and the LTV:CAC ratio.

The formula

MRR=customers×ARPU
LTV=ARPUchurn
MRR = customers × ARPU; ARR = MRR × 12; LTV = ARPU / churn; LTV:CAC = LTV / CAC
MRR
— customers × ARPU
ARR
— MRR × 12
LTV
— ARPU / monthly churn rate
payback
— CAC / ARPU (months)

Worked example

The scenario

500 customers, $50 ARPU, 3% monthly churn, $300 CAC.

gives

The result

MRR: $25,000. ARR: $300,000. LTV: ~$1,667. CAC payback: 6 months. LTV:CAC: 5.6:1.

Common use cases

  • SaaS founders tracking core growth and unit-economics metrics.
  • Evaluating whether customer acquisition is profitable.
  • Setting targets for churn reduction and ARPU expansion.

Limitations & assumptions

  • LTV here uses revenue; gross-margin LTV (× margin) is more conservative and accurate.
  • Assumes a constant churn rate; real churn varies by cohort and over time.
  • Does not model expansion revenue (upsells) or negative net churn.

Frequently asked questions

A common formula is ARPU divided by the monthly churn rate, which equals ARPU × average customer lifespan. For a profit view, multiply by gross margin.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.