MRR Growth Calculator
Decompose monthly recurring revenue into new, expansion, contraction and churn — then read the quick ratio and net revenue retention, which is the number that decides whether you grow without selling.
MRR Growth Calculator
Results recalculate instantly on every keystroke. Nothing you type is transmitted.
What this result does not account for
- Period-based; within-period joiners and leavers need a cohort view.
- Assumes movements are correctly categorised — downgrades are not churn.
- ARR is a run-rate, not a forecast.
In short: Net revenue retention decides whether you grow standing still. At 99.7371% this base shrinks by 470 a month with no new sales — the quick ratio of 3.0898 says growth is working, but it is all coming from acquisition.
Formula
net new = new + expansion − contraction − churn
NRR = (start + expansion − contraction − churn) ÷ start
[('quick ratio', 'gained ÷ lost — 4 is the benchmark'), ('NRR', 'existing customers only, can exceed 100%'), ('GRR', 'losses only, can never exceed 100%'), ('the gap', 'exactly what expansion contributes')]
Worked Example
- Record all four movements separately.
- Net them for net new MRR.
- Divide gains by losses for the quick ratio.
- Compute retention on existing customers only.
- Read where the base lands with no new sales.
178,800 of starting MRR gains 14,200 new and 6,100 expansion while losing 2,400 contraction and 4,170 churn — 13,730 net new, taking MRR to 192,530 and a 7.6789% monthly growth rate. The quick ratio is 20,300 gained over 6,570 lost = 3.0898, below the 4 benchmark, so a meaningful share of acquisition is replacing losses. Net revenue retention is 99.7371% against gross retention of 96.3255% — expansion contributes 3.4116 points but does not quite close the gap, so with no new sales the base would shrink 470 next month.
Strengths & Limits Of This Model
Where this engine is strong
- Decomposes growth into all four movements
- Separates net from gross retention and prices the gap
- Shows where the base lands with no new sales
Where it stops
- Period rather than cohort
- Categorisation-sensitive
Practical Use Cases
Board reporting
Decomposing growth into its four movements.
Judging growth efficiency
Reading the quick ratio.
Diagnosing retention
Separating net from gross retention.
Testing dependence on acquisition
Seeing where the base lands with no new sales.
Feeding LTV
Supplying the revenue-churn figures.
Methodology & Editorial Standards
All four MRR movements are entered as positive amounts and the calculation applies the signs, which prevents the common error of double-negating a loss. The quick ratio divides gains by losses. Net revenue retention deliberately excludes new business, since its purpose is to measure the existing base alone, and gross retention is computed alongside so the expansion contribution is visible as the gap. Losses exceeding the starting base are refused, since that indicates within-period churn belonging in a cohort view.
Computation runs in IEEE-754 double precision at full internal precision; rounding to two decimal places occurs strictly at the display layer, so no cumulative drift enters the result. All monetary outputs use accounting presentation — grouped thousands, two decimals, negatives in parentheses — so figures can be transcribed directly into a model or working paper. Division-by-zero and out-of-domain inputs return an em-dash rather than a misleading number.
This engine was reconciled against an independent reference implementation and hand-verified for the worked example above before release. Our full five-stage review process is published on the About Us page.
Disclaimer. This calculator is provided for informational and modelling purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Verify all figures with a qualified professional before acting on them.
MRR Growth Calculator — 10 Expert FAQs
10 analyst-written answers to the questions practitioners actually ask — optimised for voice and answer-engine retrieval.
What is net new MRR?
New plus expansion less contraction and churn. Reporting only new MRR is how growth gets overstated — a business adding fourteen thousand in new business while losing six and a half thousand has grown by the difference, not by the headline.
What is the SaaS quick ratio?
Gained MRR divided by lost MRR. Above four is the efficient-growth benchmark; between one and four you are growing but spending a large share of acquisition replacing losses; at or below one you are not growing at all.
What is net revenue retention?
Starting MRR plus expansion less contraction and churn, divided by starting MRR, counting existing customers only. Above one hundred per cent means the base grows without a single new sale, which is the strongest signal in subscription economics.
How does NRR differ from GRR?
Gross revenue retention counts only losses and can never exceed one hundred per cent. Net retention adds expansion and can. The gap between them is precisely what expansion contributes, and it is worth watching separately.
Can net retention hide a problem?
Yes. Strong net retention with weak gross retention means you are expanding a leaking base — a small number of growing accounts masking widespread churn. That works until the expanding accounts themselves churn, and then it unwinds quickly.
What is negative churn?
When expansion from existing customers exceeds all losses, so net revenue retention exceeds one hundred per cent and the base grows unaided. It is genuinely valuable and it also breaks the standard lifetime value formula, which cannot handle a negative denominator.
Should downgrades count as churn?
No — they are contraction, and the distinction matters. A customer who downgrades is retained and may upgrade again; a churned customer is gone. Booking a downgrade as churn plus new business inflates both figures and destroys the reconciliation.
Is ARR just MRR times twelve?
Arithmetically yes, conceptually no. ARR is a run-rate stating what a year would produce if nothing changed, which it will. Businesses with meaningful seasonality or annual contracts should be especially careful presenting it as a forecast.
What growth rate should I target?
It depends entirely on stage and market, and a single benchmark misleads. What matters more is the composition: growth from expansion is cheaper and more durable than growth from acquisition, because it carries no acquisition cost at all.
How do I improve net revenue retention?
Expansion revenue and contraction prevention, in that order. Usage-based or seat-based pricing lets accounts grow with the customer automatically, which is why those models routinely post retention above one hundred per cent while flat-fee models struggle to.