# SaaS metrics calculator: MRR, ARR, churn, LTV:CAC, payback and NRR

> MRR is paying customers × average revenue per account (ARPA); ARR is MRR × 12. Monthly churn is customers lost ÷ customers at the start of the month. LTV = ARPA × gross margin ÷ churn rate, and a healthy SaaS business usually aims for an LTV:CAC ratio of 3:1 or better with CAC paid back within about 12 months.

- Interactive version: https://infikeytechnologies.com/tools/saas-metrics-calculator
- Type: free instant calculator
- Category: SaaS
- Last reviewed: 2026-10-05
- Publisher: Infikey Technologies (https://infikeytechnologies.com)

## Example result (default inputs)

| Input | Value |
| --- | --- |
| Currency | USD ($) |
| Paying customers at start of month | 200 |
| Average revenue per account per month (ARPA) | 99 |
| New customers this month | 20 |
| Customers lost this month | 6 |
| Expansion MRR (upgrades, add-ons) | 500 |
| Contraction MRR (downgrades) | 100 |
| Gross margin | 80% |
| Customer acquisition cost (CAC) | 600 |

**Monthly recurring revenue (MRR): $19,800.** MRR is $19,800 (ARR $237,600) with 3% monthly customer churn and an LTV:CAC ratio of 4.4:1.

Healthy: LTV:CAC of 4.4:1 meets the common 3:1 benchmark, with CAC paid back in 7.6 months.

| Metric | Value |
| --- | --- |
| Annual recurring revenue (ARR) | $237,600 |
| Net new MRR this month | $1,786 |
| MRR at start of next month | $21,586 |
| Customer churn (monthly) | 3% |
| Annual customer retention | 69.4% |
| Gross revenue churn (monthly) | 3.51% |
| Net revenue retention (monthly / annualised) | 99% / 88.9% |
| Customer lifetime value (LTV) | $2,640 |
| LTV:CAC ratio | 4.4:1 |
| CAC payback period | 7.6 months |

### MRR movement this month

| Item | Value | Detail |
| --- | --- | --- |
| MRR at start of month | $19,800 |  |
| New customers | +$1,980 | 20 × $99.00 |
| Expansion | +$500 |  |
| Contraction | -$100 |  |
| Churned | -$594 | 6 customers |
| MRR at start of next month (selected) | $21,586 |  |

- One month of data is noisy. Average churn and expansion over 3–6 months for planning.

Open this result on the website: https://infikeytechnologies.com/tools/saas-metrics-calculator?currency=USD&customers=200&arpa=99&new_customers=20&churned=6&expansion=500&contraction=100&margin=80&cac=600

## Use from a link or API

Add these query parameters to https://infikeytechnologies.com/tools/saas-metrics-calculator (pre-filled page), https://infikeytechnologies.com/tools/saas-metrics-calculator.md (this plain-text page) or https://infikeytechnologies.com/api/tools/saas-metrics-calculator (JSON).

| Parameter | Meaning | Accepted values |
| --- | --- | --- |
| `currency` | Currency | one of USD, INR, AED, GBP, EUR |
| `customers` | Paying customers at start of month | number from 1 to 100000000, default 200 |
| `arpa` | Average revenue per account per month (ARPA) | number from 0 to 10000000 (in the chosen currency), default 99 |
| `new_customers` | New customers this month | number from 0 to 100000000, default 20 |
| `churned` | Customers lost this month | number from 0 to 100000000, default 6 |
| `expansion` | Expansion MRR (upgrades, add-ons) | number from 0 to 1000000000 (in the chosen currency), default 500 |
| `contraction` | Contraction MRR (downgrades) | number from 0 to 1000000000 (in the chosen currency), default 100 |
| `margin` | Gross margin | number from 1 to 100 (%), default 80 |
| `cac` | Customer acquisition cost (CAC) | number from 0 to 100000000 (in the chosen currency), default 600 |

- Early-stage startup: https://infikeytechnologies.com/tools/saas-metrics-calculator?currency=USD&customers=50&arpa=49&new_customers=10&churned=3&expansion=0&contraction=0&margin=75&cac=300
- Growing SMB SaaS: https://infikeytechnologies.com/tools/saas-metrics-calculator?currency=USD&customers=800&arpa=79&new_customers=70&churned=24&expansion=1500&contraction=400&margin=80&cac=450
- Enterprise SaaS: https://infikeytechnologies.com/tools/saas-metrics-calculator?currency=USD&customers=120&arpa=2500&new_customers=4&churned=1&expansion=15000&contraction=2000&margin=85&cac=30000

## How it is calculated

- **MRR**: paying customers × ARPA
- **ARR**: MRR × 12
- **Customer churn**: customers lost ÷ customers at start of month
- **Net revenue retention**: (MRR + expansion − contraction − churned MRR) ÷ MRR
- **LTV**: ARPA × gross margin ÷ monthly churn rate
- **CAC payback**: CAC ÷ (ARPA × gross margin) months

## Benchmarks founders and investors look at

These are rules of thumb used widely in SaaS, not guarantees. Compare against companies with a similar price point and customer size.

| Metric | Commonly cited target | Why it matters |
| --- | --- | --- |
| LTV:CAC | 3:1 or higher | Below 1:1 you lose money on every customer; far above 5:1 may mean you are under-investing in growth. |
| CAC payback | Under 12 months | Shorter payback means growth needs less cash. |
| Net revenue retention | Above 100% | Existing customers grow revenue even before new sales. |
| Monthly customer churn | Lower is better; depends on segment | Small-business products churn faster than enterprise contracts. |

## Customer churn vs revenue churn

Customer churn counts accounts lost; revenue churn counts the MRR lost, including downgrades. If larger customers stay and small ones leave, revenue churn can be lower than customer churn.

Net revenue retention adds expansion revenue back. When NRR is above 100%, upgrades from existing customers outweigh everything lost to churn and downgrades.

## Ways to improve the numbers

- Shorten time-to-value with guided onboarding — most churn happens in the first weeks.
- Offer annual plans to lock in retention and improve cash flow.
- Add usage-based or tiered pricing so revenue grows with the customer.
- Track product usage to spot at-risk accounts before they cancel.
- Lower CAC with content, SEO and referrals alongside paid acquisition.

## FAQ

### How do you calculate MRR?

Multiply the number of paying customers by the average monthly revenue per account. Annual plans count as one-twelfth of the annual price per month; one-off fees are excluded.

### How do you calculate SaaS churn rate?

Divide the customers lost during a month by the customers you had at the start of that month. 6 lost out of 200 is 3% monthly churn.

### How is customer lifetime value (LTV) calculated for SaaS?

LTV = ARPA × gross margin ÷ monthly churn rate. With $99 ARPA, 80% margin and 3% churn, LTV is about $2,640.

### What is a good LTV:CAC ratio?

A ratio of 3:1 or higher is the commonly cited benchmark: each customer returns at least three times what it cost to acquire them, in gross profit.

### What is net revenue retention (NRR)?

NRR measures how revenue from existing customers changes over time, including upgrades, downgrades and cancellations. Above 100% means the existing base grows on its own.

### What is the difference between MRR and ARR?

ARR is simply MRR × 12. MRR suits monthly plans and early-stage tracking; ARR is common for annual contracts and investor reporting.

## Get expert help

Send these results to an Infikey Technologies specialist from the form on https://infikeytechnologies.com/tools/saas-metrics-calculator#estimate or via https://infikeytechnologies.com/contact.

More free calculators: https://infikeytechnologies.com/tools.md

## Disclaimer

This calculator is provided free for general information and planning only. Results are estimates based on the inputs you enter and the assumptions described on this page, reference data such as published prices may change, and actual costs and outcomes will differ. Nothing on this page is financial, legal, tax, investment or other professional advice. Infikey Technologies Private Limited, Infikey Technologies LLC and their directors, employees and affiliates make no warranty, express or implied, about the accuracy, completeness or suitability of this tool or its results, and accept no liability for any loss or damage, direct or indirect, arising from its use or from reliance on its results. Verify all figures independently and seek professional advice before making any decision. Use of this tool is at your own risk.