Plug in last month's revenue and customer movements. Get a full SaaS metrics readout — net new MRR, NRR, GRR, churn, ARPU, ARR — and a 12-month compound projection.
NRR benchmarks
≥120%: Best-in-class.
100–120%: Healthy.
90–100%: Marginal.
<90%: Leaky bucket — fix retention before scaling acquisition.
NRR vs GRR gap
If NRR is 120% but GRR is 85%, expansion is masking serious churn. Always look at both — high NRR alone can hide a leaky bucket. A small gap (NRR-GRR < 10pp) usually means stable retention with modest upsell.
Customer vs revenue churn
When revenue churn exceeds customer churn, your biggest customers are leaving. When the reverse is true, it's small accounts churning — less urgent but still worth investigating.
MRR (Monthly Recurring Revenue) is the predictable subscription revenue you bill in a month. ARR (Annual Recurring Revenue) is simply MRR × 12 — the annualized run rate. ARR is what investors and boards focus on; MRR is what operators track day-to-day. Both exclude one-time charges, services revenue, and non-recurring fees.
Net Revenue Retention measures how much revenue you keep from your starting customer base after a period, including expansions, contractions, and churn. NRR = (Starting MRR + Expansion − Contraction − Churn) ÷ Starting MRR. Best-in-class SaaS hit 120%+, healthy is 100–120%, marginal is 90–100%, and below 90% signals serious retention issues.
Gross Revenue Retention measures retention without expansion — it's the floor. GRR = (Starting MRR − Contraction − Churn) ÷ Starting MRR. It can never exceed 100%. NRR includes expansion, so it can exceed 100%. The gap between NRR and GRR tells you how much expansion is masking churn. A company at 120% NRR but 85% GRR has serious retention problems hidden by upsell.
Customer churn rate = customers lost ÷ starting customer count. Revenue churn rate = revenue lost ÷ starting MRR. They diverge when churned customers have different ARPU than average. If your largest customers churn, revenue churn is much higher than customer churn — a much bigger problem than the count suggests.
100% NRR means your existing customer base generates the same revenue this month as last month — expansion exactly offsets contraction and churn. Net new growth comes entirely from new customer acquisition. Above 100%, your existing customers grow with you. Below 100%, you have a leaky bucket — you're acquiring just to replace lost revenue.
The projection assumes your current monthly net new MRR growth rate compounds for 12 months. It's the simplest possible forward-look — what "maintaining this month's pace" produces over a year. Real growth is rarely smooth; use this as a planning anchor, not a forecast.
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