SaaS metrics: what to measure, and what each number can and cannot tell you
SaaS metrics are the shared vocabulary of founders, investors, lenders, and acquirers. They are also easy to misuse. Two companies can both report "$20,000 MRR" while measuring very different things: one counts normalized active subscriptions, the other counts every payment that landed in the last 30 days. A useful metrics practice starts with written definitions, consistent measurement dates, and a clear link from each number back to source records.
This reference covers the SaaS metrics most often requested in fundraising, lending, and acquisition conversations. Each section gives a formula, a short worked example, the most common mistake, and a link to a deeper guide or calculator. None of these metrics are GAAP measures, and nothing here is accounting or tax advice; use a qualified accountant when figures feed financial statements, tax filings, or a purchase agreement.
Start with definitions, not dashboards
Before calculating anything, write down:
- The measurement date or period. "MRR on 30 September" and "average MRR in Q3" are different numbers.
- What counts as recurring. Setup fees, consulting, one-time purchases, lifetime deals, and usage overages may or may not belong in recurring metrics.
- How refunds, disputes, discounts, taxes, and currency conversion are treated.
- Whether figures are before or after payment-provider fees.
Stripe's own documentation is a good example of an explicit definition: it calculates MRR by summing the monthly-normalized amounts of active and past-due subscriptions, excludes trialing subscriptions and one-time invoices, and calculates ARR as MRR × 12 (Stripe Support, "Understanding MRR and ARR"). Your definition may differ, but it should be that specific.
Revenue metrics
MRR (monthly recurring revenue)
MRR = sum of monthly-normalized recurring subscription amounts at a measurement date
A customer on a $1,200 annual plan contributes $1,200 ÷ 12 = $100 of MRR, not $1,200 in the month they paid. Track MRR movements separately: new, expansion, contraction, churned, and reactivated. Read more in what is MRR.
Common mistake: treating a processor's monthly payment total as MRR. Annual prepayments, one-time sales, and refunds can make the two diverge sharply.
ARR (annual recurring revenue)
ARR = MRR × 12 (or the annualized value of active recurring contracts)
ARR is a scale metric for subscription businesses, not a measure of cash collected or profit. Andreessen Horowitz's "16 Startup Metrics" warns against annualizing one month's bookings and stresses that ARR should exclude one-time fees (a16z, "16 Startup Metrics"). See MRR vs ARR and the MRR and ARR calculator.
Trailing revenue and TTM revenue
Trailing revenue sums what was actually recorded over a lookback window. RevenueBug's headline is trailing 30-day revenue: successful payment principal minus refunds and disputes, before provider fees, for qualifying payments from a connected provider. It can include one-time sales and annual payments, so it is not necessarily subscription MRR (methodology).
TTM revenue = sum of revenue recognized or recorded in the last 12 complete months
TTM smooths seasonality and annual-renewal lumps and is the usual denominator for earnings-based valuations. See TTM revenue.
Gross vs net revenue
Gross and net revenue are defined differently by accountants, payment dashboards, and marketplaces. Write down whether your revenue line is before or after refunds, discounts, disputes, taxes, and processor or platform fees. See gross vs net revenue.
Retention and churn metrics
Customer (logo) churn
Monthly logo churn = customers lost during the month ÷ customers at start of month
If you start March with 400 customers and lose 12, logo churn is 12 ÷ 400 = 3%. Exclude customers who joined during the month from the denominator. See how to calculate churn rate and SaaS churn benchmarks.
Revenue churn, GRR, and NRR
Gross revenue retention (GRR) = (starting MRR − churned MRR − contraction MRR) ÷ starting MRR
Net revenue retention (NRR) = (starting MRR − churned − contraction + expansion) ÷ starting MRR
Example: a cohort starts with $50,000 MRR, loses $3,000 to cancellations and $1,000 to downgrades, and adds $5,500 in upgrades a year later. GRR is ($50,000 − $3,000 − $1,000) ÷ $50,000 = 92%; NRR is ($50,000 − $4,000 + $5,500) ÷ $50,000 = 103%.
For context, SaaS Capital's 2025 survey of private B2B SaaS companies reported a median NRR of 102% for companies with annual contract values between $25,000 and $50,000 (SaaS Capital, 2025 retention benchmarks). Those companies are larger and more sales-led than most micro-SaaS products, so treat that as context, not a target. See net revenue retention and the churn and retention calculator.
Unit-economics metrics
CAC (customer acquisition cost)
CAC = sales and marketing cost in a period ÷ new customers acquired in that period
Spending $12,000 on ads, content contractors, and sales tools in a quarter that produces 60 new customers gives $12,000 ÷ 60 = $200 blended CAC. The a16z piece recommends tracking paid CAC separately from blended CAC, because organic signups can hide unprofitable paid channels (a16z).
LTV and LTV:CAC
LTV ≈ (ARPA × gross margin) ÷ monthly revenue churn
With $50 ARPA, 80% gross margin, and 2.5% monthly revenue churn, LTV is ($50 × 0.80) ÷ 0.025 = $1,600, and LTV:CAC against a $200 CAC is 8:1. David Skok's widely cited guideline is an LTV:CAC above 3 and CAC recovered in under 12 months (For Entrepreneurs, "SaaS Metrics 2.0"). See LTV:CAC ratio and the LTV:CAC calculator.
CAC payback period
CAC payback (months) = CAC ÷ (ARPA × gross margin)
Using the numbers above: $200 ÷ ($50 × 0.80) = 5 months. Payback is less sensitive to churn assumptions than LTV, which is why many operators prefer it.
Gross margin
Gross margin = (revenue − cost of revenue) ÷ revenue
Include hosting, third-party APIs (including AI inference), payment fees if you treat them as cost of revenue, and customer support directly tied to delivery. The a16z article notes that all costs of delivering and supporting the service belong in the calculation and that founders should be able to explain what is included (a16z). AI-heavy products in particular can have materially lower margins than classic SaaS.
Growth and efficiency metrics
Growth rate
Month-over-month growth = (MRR this month ÷ MRR last month) − 1
Year-over-year growth = (MRR this month ÷ MRR same month last year) − 1
Prefer year-over-year or trailing three-month averages for small products, where one large customer can swing a single month.
SaaS quick ratio
Quick ratio = (new MRR + expansion MRR) ÷ (churned MRR + contraction MRR)
If you add $4,000 and lose $1,600, the quick ratio is 2.5. It describes growth efficiency, not absolute scale. See SaaS quick ratio.
Rule of 40
Rule of 40 score = revenue growth rate (%) + profit margin (%)
A company growing 25% with a 20% margin scores 45. Teams use different margin definitions (EBITDA, free cash flow, operating margin), so state yours. Test scenarios with the Rule of 40 calculator.
Burn and runway
Runway (months) = cash on hand ÷ average monthly net burn
$90,000 of cash and $7,500 of net burn give 12 months. Model hiring and pricing changes in the startup runway calculator.
Profit metrics buyers use: SDE and EBITDA
Smaller acquisitions are often priced on earnings rather than revenue.
SDE = pre-tax profit + one owner's compensation + supportable add-backs
EBITDA = net income + interest + taxes + depreciation + amortization
SDE suits owner-operated businesses; EBITDA suits businesses with management in place. See SDE vs EBITDA, micro-SaaS valuation, and ARR multiples.
How to present metrics to buyers or investors
- Show the definitions next to the numbers. A one-page metric glossary prevents most diligence disputes.
- Reconcile. Billing-system MRR should reconcile to payment-provider data, bank deposits, and the general ledger.
- Show trends, not snapshots. Twelve to twenty-four months of monthly MRR movements, cohorts, and churn are more informative than one good month.
- Separate verified from self-reported. A verified revenue profile built from a connected provider reduces doubt about the revenue input. It does not verify profit, churn quality, ownership, or valuation.
If you are preparing for a sale, the prepare a startup for sale guide lists the reports buyers typically request.
Frequently asked questions
Which SaaS metrics matter most at an early stage?
MRR (or trailing revenue if you are not subscription-based), logo churn, revenue retention, and gross margin. CAC and LTV become meaningful once you have a repeatable acquisition channel and enough customer history to estimate churn.
Are SaaS metrics GAAP measures?
No. MRR, ARR, NRR, CAC, and LTV are operating metrics without a standardized GAAP definition. Public companies that report them define them in their own filings. Treat any figure as meaningful only alongside its definition.
Is trailing 30-day revenue the same as MRR?
Not necessarily. Trailing revenue sums payments recorded in a window and can include one-time and annual payments. MRR normalizes active subscriptions to a monthly amount. For a business with only monthly plans and few refunds, the two can be close; otherwise they can differ significantly.
How often should I calculate these metrics?
Monthly is standard for MRR, churn, and retention. Calculate CAC and payback by quarter if monthly volumes are small. Recalculate TTM figures monthly on a rolling basis.
Do benchmarks from SaaS surveys apply to micro-SaaS?
Use them cautiously. Most published surveys cover venture-backed or sales-led B2B companies with larger contracts. A low-priced self-serve product may have higher logo churn and lower NRR while still being a healthy, profitable business.
What should I fix first if my metrics look weak?
Retention usually comes first: improving churn raises LTV, shortens the effective payback, and makes growth compound. Then check gross margin and pricing before increasing acquisition spend.