SaaS Metrics Calculator
Enter one month of revenue and customer movement. Get every core SaaS metric — MRR, ARR, churn, retention, LTV, CAC, payback and Quick Ratio — with benchmarks so you know if each number is healthy.
What this calculator works out
SaaS performance comes down to a handful of numbers that build on each other. This tool takes one month of revenue and customer movement and derives all of them, then flags whether each is in a healthy range.
Revenue: MRR and ARR
Ending MRR = starting MRR + new MRR + expansion MRR − contraction MRR − churned MRR. ARR is simply ending MRR × 12. Net new MRR is the change over the month (everything except starting MRR), and the MRR growth rate expresses that as a percentage of where you started.
ARPA
Average Revenue Per Account = ending MRR ÷ ending customers. It underpins both LTV and CAC payback, so a stable or rising ARPA quietly improves everything downstream.
Churn: gross vs net
Gross MRR churn = (churned MRR + contraction MRR) ÷ starting MRR — money lost from the existing base, best kept as low as possible. Net MRR churn subtracts expansion MRR from the same numerator; when upgrades outweigh losses it goes negative, which is the hallmark of a strong product. Customer (logo) churn = customers lost ÷ starting customers, and its inverse is the average customer lifetime in months.
Retention: NRR and GRR
GRR = (starting MRR − contraction − churned) ÷ starting MRR. It caps at 100% and shows how sticky your revenue is before any upsell. NRR adds expansion back in, so a figure above 100% means the existing base grows on its own, before a single new customer.
Unit economics: CAC, LTV, payback, Quick Ratio
CAC = sales & marketing spend ÷ new customers acquired. LTV = (ARPA × gross margin) ÷ monthly logo churn. LTV:CAC compares the two. CAC payback = CAC ÷ (ARPA × gross margin), in months. The Quick Ratio = (new + expansion MRR) ÷ (churned + contraction MRR) sums up acquisition efficiency in one number.
Benchmarks
| Metric | Healthy | Watch | Poor |
|---|---|---|---|
| Gross MRR churn (monthly) | < 3% | 3–6% | > 6% |
| Net MRR churn (monthly) | ≤ 0% | 0–3% | > 3% |
| Customer / logo churn (monthly) | < 3% | 3–6% | > 6% |
| Net revenue retention (NRR) | ≥ 105% | 90–105% | < 90% |
| Gross revenue retention (GRR) | ≥ 90% | 80–90% | < 80% |
| LTV : CAC | 3–5× | 1.5–3× (or > 5×) | < 1.5× |
| CAC payback | < 12 mo | 12–18 mo | > 18 mo |
| SaaS Quick Ratio | ≥ 4 | 2–4 | < 2 |
These are rough SMB-SaaS norms. Enterprise businesses run much lower churn; early-stage companies with tiny denominators see wild swings month to month. Use a rolling 3-month average for anything you report.
Frequently asked questions
What is a good LTV:CAC ratio for SaaS?
A ratio around 3:1 is the common rule of thumb: each customer is worth about three times what you spent to acquire them. Below 1:1 you lose money on every customer. Well above 5:1 often means you are under-investing in growth and could spend more on acquisition.
How do you calculate SaaS churn rate?
Customer (logo) churn = customers lost in the period ÷ customers at the start. Gross MRR churn = (churned MRR + contraction MRR) ÷ starting MRR. Net MRR churn subtracts expansion MRR from that numerator, so strong upgrades can push it to zero or negative.
What is the difference between gross and net revenue retention?
Gross Revenue Retention (GRR) measures how much starting MRR you keep after downgrades and cancellations — it can never exceed 100%. Net Revenue Retention (NRR) also adds expansion revenue from existing customers, so it can exceed 100% when upgrades outweigh losses.
What is the SaaS Quick Ratio?
Quick Ratio = (new MRR + expansion MRR) ÷ (churned MRR + contraction MRR). It shows how efficiently you add recurring revenue versus losing it. Above 4 is strong; below 1 means revenue is shrinking.
How is CAC payback period calculated?
CAC payback (in months) = CAC ÷ (ARPA × gross margin). It is the number of months of gross profit from an average customer needed to recover what you spent acquiring them. Under 12 months is generally healthy for SMB SaaS.
Do the numbers I enter get sent anywhere?
No. The calculator runs entirely in your browser. Nothing you type is uploaded or stored on a server.