MRR Growth Calculator: Project SaaS Revenue, Churn & NRR

Project Monthly Recurring Revenue forward from new and churned MRR trends, and track net revenue retention.

Real SaaS churn scales with how much MRR you have — losing 5% of a shrinking base is a smaller dollar figure than losing 5% of a growing one — but this modeler works the other way around: you enter flat dollar amounts for new MRR and churned MRR per month, and it projects those same two numbers forward unchanged for the entire horizon. That's a deliberately simple model, and knowing that is the key to reading its output correctly.

How to use the MRR growth calculator

Enter starting MRR: the recurring revenue you bill in the current month.
Enter new MRR added per month, counting expansion from upgrades as well as revenue from brand-new customers.
Enter churned MRR per month, counting downgrades (contraction) along with cancellations.
Pick a 6, 12, 24 or 36 month horizon.
Read ending MRR, net MRR change per month, NRR and the Growing, Flat or Shrinking trend, then check the chart for the shape of the line.

The projection adds and subtracts the same two numbers every month

Starting from your entered starting MRR, each projected month adds new MRR per month and subtracts churned MRR per month — a flat net change repeated identically for every month in the horizon, not a percentage growth rate compounding against a moving balance. Six, twelve, twenty-four, and thirty-six month horizons are all available, and the projection is the same starting balance plus that flat net change multiplied out.

This additive shape is easy to reason about and easy to get wrong for the same reason: if your actual churned-MRR dollar figure is really a percentage of current MRR rather than a fixed amount, holding it flat here will understate churn as your MRR grows and overstate it as your MRR shrinks.

The MRR movement formula

SaaS reporting usually splits each month into five movements: ending MRR = starting MRR + new + expansion − churned − contraction. This calculator takes two inputs instead of four, so fold expansion into the new MRR figure and contraction into the churned figure; the net change it reports is simply new minus churned.

Example: $20,000 starting MRR with $3,000 of new business, $500 of expansion, $1,200 of cancellations and $300 of downgrades becomes $3,500 new and $1,500 churned. That is a $2,000 net gain each month and $32,000 ending MRR after six months, with NRR shown as 92.5%.

Net Revenue Retention is a single snapshot, not a running figure

NRR is computed once, from your starting MRR and your entered monthly churned MRR — (starting MRR minus churned MRR) divided by starting MRR — rather than recalculated for each projected month as the balance moves. It's a useful single-number summary of how much of your existing base you're retaining before new sales are counted at all, but it doesn't track how that retention percentage might shift over a multi-year projection.

A negative trend flag trips whenever churned MRR per month exceeds new MRR per month — the projection is shrinking overall even before you look at the chart, which is worth noticing before you scroll down to see just how far the line falls by month thirty-six.

Two cautions before you compare it with published NRR figures. It is a one-month number, while most benchmarks quote NRR over twelve months. And because expansion is folded into new MRR, it never adds upsell revenue back, so it behaves like gross revenue retention and can never exceed 100% here, even for a business whose customers grow their spend every month.

Churn MRR vs churn rate

Churned MRR is a dollar amount: the recurring revenue lost to cancellations and downgrades in a month. The churn MRR rate expresses that same loss as a share of the MRR you started the month with, so losing $1,500 from a $20,000 base is a 7.5% rate.

The calculator asks for the dollar figure and holds it flat, which means the implied rate quietly falls as MRR grows. If your churn behaves like a steady percentage, re-run the projection with a larger churned figure once your base has grown.

SaaS MRR benchmarks

These are market reference points from investors and industry commentary, not targets the calculator checks you against; compare yourself with companies of similar size and customer type.

Early growth: Paul Graham's essay 'Startup = Growth' calls 5–7% a week a good rate for a startup in Y Combinator, a pace very few companies sustain beyond their first year.
Scaling growth: Battery Ventures' Neeraj Agrawal described T2D3, tripling ARR two years running and then doubling three times, as a path for venture-scale SaaS.
Net revenue retention: above 100% means expansion outruns churn and downgrades; investors often describe 120% or more as best-in-class for enterprise SaaS, while SMB products commonly sit lower.
Monthly revenue churn: figures around 3–7% a month are often quoted for SMB-focused SaaS, whereas enterprise contracts are expected to churn well under 1% a month.

What a flat-rate model can't show you

It cannot represent expansion revenue and new-logo revenue as separate lines — both are folded into a single 'new MRR per month' figure, so you can't see how much of your growth comes from existing customers upgrading versus brand-new customers.
It cannot model churn accelerating or decelerating over the projection window; whatever churned-MRR figure you enter for month one is the same figure applied at month thirty-six.
It has no concept of cohort-level retention curves, seasonality, or one-time events like a large customer's contract renewal falling in a specific month.
For a board-ready forecast or a fundraising deck, use this as a quick sanity check on direction, not as the model itself — a real SaaS financial model needs cohort-level data this tool never asks for.

Reading the chart honestly

A rising line means new MRR is currently outpacing churned MRR at the flat rates you entered — it says nothing about whether that gap will hold as your business scales, since the model has no mechanism for either number to change with your growing or shrinking base.

If your business is small, a flat-dollar model is often a reasonable short-term approximation because a fixed number of new or lost logos each month genuinely does look roughly linear over six or twelve months. The approximation breaks down fastest at the longer horizons, which is exactly where the modeler's simplicity matters most.

Questions people ask about MRR Growth & Churn Modeler

Does churned MRR increase as my MRR grows, like a real churn rate would?: No. Churned MRR per month is a flat dollar figure you enter once, and the projection subtracts that same amount every month regardless of how large the running balance has grown. If your real churn behaves as a percentage of current MRR, this model will understate the dollar impact as you scale.
Why is NRR shown as one number instead of changing over the projection?: NRR is calculated once from your starting MRR and monthly churned MRR figure as a snapshot of current retention, not recomputed for each projected month. It's meant to summarize where you stand today, not to track how retention might shift as the linear projection runs forward.
What does the negative-trend warning actually mean?: It means the churned MRR per month you entered is larger than the new MRR per month you entered, so the flat monthly math nets out to a shrinking balance for the entire horizon — worth investigating before relying on any longer-term number the chart shows past that point.
Can I use this to build a real SaaS financial model for investors?: Use it as a quick directional sanity check, not as your actual model. A model an investor or board expects will separate new-logo and expansion revenue, model churn as a percentage of current MRR, and account for cohort-level retention curves — none of which this simplified flat-rate projection attempts to do.
What is a good MRR growth rate?: It depends on stage and size. Very young startups are judged on weekly or month-over-month growth, with double-digit monthly percentages often described as strong, while established companies are measured on annual ARR growth against patterns such as Battery Ventures' T2D3. Compare yourself with companies at a similar revenue level.
What churn rate should a SaaS company target?: Lower is always better, but the realistic target depends on who you sell to. SMB products commonly lose several percent of MRR each month, while enterprise contracts are often expected to churn well under 1% monthly. The strongest position is net negative churn, where expansion outweighs what you lose.
Do downgrades count as churned MRR?: In most SaaS reporting, yes: revenue lost when a customer moves to a cheaper plan is called contraction and is grouped with cancellations as lost MRR. In this calculator, include downgrades in the churned MRR per month figure so that the net change and the NRR both reflect them.
What's the difference between churn MRR and churn MRR rate?: Churn MRR is the dollar amount of recurring revenue lost in a month; the churn MRR rate divides that amount by starting MRR. The calculator takes the dollar figure, and you can read the rate straight off the result as 100% minus the NRR it displays.

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Content reviewed 2026-09-27.