Last updated: March 2026

MRR & ARR Calculator

Calculate Monthly Recurring Revenue, Annual Recurring Revenue and MRR movement metrics

What is MRR (Monthly Recurring Revenue)?

Monthly Recurring Revenue (MRR) is the lifeblood metric of any subscription or SaaS business. It represents the total predictable, normalised revenue generated every month from active subscriptions. Unlike one-time sales, MRR recurs — making it the single most important indicator of a company's financial health and growth trajectory.

The formula is elegantly simple: MRR = Number of Active Subscribers × Average Revenue Per Account (ARPA). If you have 400 customers each paying £150 per month, your MRR is £60,000. If some customers are on annual plans, normalise them: a £1,800/year contract contributes £150 MRR.

MRR vs ARR: Which Should You Use?

Annual Recurring Revenue (ARR) is simply MRR multiplied by 12. Both measure the same underlying business health — the difference is the lens through which you look:

MetricBest Used ForTypical Users
MRRMonthly growth tracking, churn monitoring, cohort analysisEarly-stage, high-growth SaaS (pre-Series B)
ARRInvestor reporting, annual planning, valuation multiplesSeries A+, enterprise SaaS, VC reporting

Neither MRR nor ARR is the same as GAAP revenue. A customer who pays £12,000 upfront for an annual plan contributes £1,000 MRR but the full £12,000 is received as cash today. MRR/ARR represent run-rate revenue, not cash received.

The Five Components of MRR

Understanding MRR movement requires breaking it into five components:

  • New MRR — Revenue from brand-new customers acquired this month
  • Expansion MRR — Revenue from existing customers upgrading to higher tiers or purchasing add-ons
  • Contraction MRR — Revenue lost from existing customers downgrading to lower tiers
  • Churned MRR — Revenue lost from customers who cancelled entirely
  • Reactivation MRR — Revenue from previously churned customers returning

Net New MRR = New MRR + Expansion MRR + Reactivation MRR − Contraction MRR − Churned MRR. Ending MRR = Starting MRR + Net New MRR.

SaaS Quick Ratio Explained

The Quick Ratio measures growth efficiency — how many pounds of MRR you gain for every pound you lose. It was popularised by Mamoon Hamid at Kleiner Perkins as a simple VC benchmark:

Quick Ratio = (New MRR + Expansion MRR) ÷ (Contraction MRR + Churned MRR)
Quick RatioAssessmentMeaning
> 4ExcellentStrong growth, efficient churn management
2 – 4GoodHealthy growth, watch churn trends
1 – 2ConcerningGrowth barely outpaces churn
< 1DangerShrinking business — churn exceeds growth

MRR Benchmarks by Company Stage

StageTypical MRRARRMonthly Growth Rate
Pre-seed / Idea£0 – £5K< £60KN/A
Seed£5K – £50K£60K – £600K10–15% MoM
Series A£50K – £300K£600K – £3.6M5–10% MoM
Series B£300K – £1M+£3.6M – £12M+3–5% MoM
Growth£1M+£12M+100–150%+ YoY

MRR vs Revenue: Why SaaS Companies Use MRR

GAAP revenue recognition rules require spreading subscription revenue over the service period, which can create misleading spikes when customers pay annually upfront. MRR smooths this out, giving a cleaner view of run-rate performance. Investors and operators use MRR because it:

  • Removes seasonality from annual contract timing
  • Enables apples-to-apples comparison across different billing frequencies
  • Ties directly to unit economics (CAC payback, LTV:CAC)
  • Forms the basis for SaaS company valuation (ARR multiples, typically 5–15× ARR for high-growth companies)

Frequently Asked Questions

MRR (Monthly Recurring Revenue) is the predictable, recurring revenue a SaaS or subscription business generates each month. It is calculated as: MRR = Number of Subscribers × Average Revenue per Account (ARPA) per month. For example, 500 customers each paying £100/month = £50,000 MRR. MRR normalises annual or quarterly contracts into a monthly figure — a customer on a £1,200/year plan contributes £100 MRR. It excludes one-time fees, professional services, and non-recurring charges.

MRR (Monthly Recurring Revenue) measures recurring revenue on a monthly basis, while ARR (Annual Recurring Revenue) measures it annually. ARR = MRR × 12. MRR is most useful for tracking month-to-month momentum, especially in early-stage companies growing quickly. ARR is preferred for annual planning, investor reporting, and companies with predominantly annual contracts. Neither MRR nor ARR is the same as GAAP revenue — they represent contracted, recognised recurring revenue only.

The SaaS Quick Ratio measures growth efficiency: how much new MRR you add for every £1 of MRR lost to churn and contraction. Quick Ratio = (New MRR + Expansion MRR) ÷ (Contraction MRR + Churned MRR). A ratio above 4 is considered excellent, indicating strong growth with manageable churn. A ratio of 2–4 is good. Below 1 means you are losing more than you are gaining. Benchmark: Top-quartile SaaS companies at Series A typically have a Quick Ratio of 4+.

Net Revenue Retention (NRR) measures how much recurring revenue you retain from existing customers over a period, including expansions. NRR = (Starting MRR + Expansion MRR − Contraction MRR − Churned MRR) ÷ Starting MRR × 100%. An NRR above 100% means your existing customers are paying you more over time (upsells outweigh churn), which is the hallmark of elite SaaS businesses. NRR above 120% is exceptional and indicates strong product-market fit and expansion motion.

To normalise annual plans into MRR, divide the annual contract value (ACV) by 12. A customer paying £1,200/year contributes £100 MRR. A customer on a £600 6-month plan contributes £100 MRR. This normalisation is critical for comparing plans consistently and ensures MRR accurately represents your run-rate recurring revenue. Never count one-time implementation fees, set-up charges, or professional services in MRR — these are non-recurring revenues.

Sources: SaaS Quick Ratio methodology from Bessemer Venture Partners | MRR/ARR definitions aligned with standard SaaS accounting practices. Always verify with your finance team for investor reporting.
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