SaaS metrics calculator: see one month's MRR and retention

How to use the calculator

1. Choose one completed calendar month and one currency. From your billing report, enter starting MRR and that month's new, expansion, contraction, and churned MRR. Divide annual subscription amounts by 12 first. Leave out one-time charges, tax, and amounts that are not recurring subscription revenue. Enter 0 for a required movement that did not happen. The currency choice formats amounts; it does not convert them.
2. If you know your paying-account counts, enter all three: starting, new, and churned starting accounts. Count the same kind of customer throughout. For example, if a company is one paying account, count companies rather than seats.
3. Add recognized recurring revenue and its matching service costs together. Revenue recognized during the month differs from both cash collected and ending MRR. Acquisition spend needs the account counts. Enter net cash burn separately from your cash records: cash paid out less cash received during the month.
4. Read ending MRR first, then growth and retention, followed by any optional results. Unavailable means the supplied figures cannot produce that metric; the result gives the reason. Leave an unknown optional group blank instead of entering zero to force a result. If an input is rejected, check for an incomplete group, a number with commas or more than two decimal places, or contraction and churned MRR that together exceed starting MRR. Reconcile the source figures before calculating again.

Read the revenue and retention snapshot

Ending MRR is the monthly subscription run rate at the close of the selected month. Annualized recurring revenue (ARR) is ending MRR multiplied by 12. For example, April's $12,000 ending MRR gives $144,000 ARR. That ARR is a run rate, not revenue already earned or a promise of next year's sales. ChartMogul's MRR guide explains why annual plans are converted to monthly amounts and one-time fees are left out.

New MRR affects total growth but stays out of NRR and GRR. In the April example below, expansion replaces the MRR lost to contraction and churn, so NRR is 100%; GRR is 90% because it leaves expansion out. Five of 100 starting accounts still churned, giving 5% customer churn. Revenue retention and account churn describe different things. ChartMogul explains the starting-base rule for NRR and GRR and how to count customer churn.

If starting MRR is zero, growth, NRR, and GRR have no starting revenue to divide by. If starting paying accounts are zero, customer churn has no starting count. The calculator marks these results Unavailable rather than showing 0%. Accounts that join and leave, or leave and reactivate, within the same month need careful classification in your billing records; this simple snapshot counts churned accounts from the starting base.

Understand margin and acquisition costs

Gross margin compares recurring revenue recognized during the month with the direct costs of delivering it, often called cost of goods sold (COGS). Include relevant service costs such as hosting and customer support, using the same month's accounting basis. Gross margin does not use cash collected, and it is negative if service costs exceed recognized revenue. Monthly average revenue per account (ARPA) uses ending MRR divided by ending paying accounts, so it has a different timing basis from the recognized revenue used for margin. Stripe's SaaS metrics guide explains gross margin and service costs.

Customer acquisition cost (CAC) divides allocated sales and marketing spend by new paying accounts. A long sales cycle can make this month's spending and this month's new accounts a poor match, even when both figures are correct. Stripe's CAC guide explains that timing and cost allocation issue.

The simple LTV estimate assumes churn and margin remain steady and does not model later expansion or contraction. It combines month-end ARPA with churn measured from the starting accounts, so it is a rough estimate, not a measured customer lifetime. Zero churn does not prove infinite LTV; this formula needs a positive churn rate to produce a finite estimate. The calculator also leaves LTV and payback unavailable when gross margin is zero or negative, because the estimated monthly gross profit per account is not positive. ChartMogul describes the LTV formula and its limits.

Margin-aware CAC payback estimates how many months of gross profit from an average account would cover its acquisition cost. It divides CAC by monthly gross profit per account, rather than revenue per account. It does not track what the newly acquired accounts actually pay later. Stripe explains the profit-based payback calculation.

Read the burn multiple

The burn multiple compares the month's net cash burn with the annualized change in MRR. Enter burn from your cash records; the calculator does not derive it from the service and acquisition costs above. Craft Ventures defines burn multiple as net burn divided by net new ARR.

This compares one month's burn with a change in annualized run rate; it does not treat one month's MRR growth as annual revenue already earned. When net new MRR is zero or negative, the burn multiple is unavailable. When net cash burn is negative, the company generated cash that month, and the tool says so instead of showing a negative multiple. A single month's result can swing with payment timing and costs, so compare months with the same definitions before drawing a conclusion.

Check the figures behind the result

This manual calculator cannot verify subscription classifications, customer identity, recognized revenue, service-cost allocation, or which acquisition spending produced the new accounts. Check the source ledger and billing report when a result looks surprising. Then compare completed monthly snapshots using the same currency, paying-account unit, and cost definitions.