MRR Calculator

What Is the MRR Calculator?

The MRR Calculator is a free online tool that works out monthly recurring revenue for any subscription business. MRR is the predictable revenue you expect every month from paying customers, before one-time fees and variable usage charges. Investors ask for it, founders plan hiring against it, and teams set growth targets from it, because it smooths the noise of annual prepayments and one-off sales into a single comparable number.

You enter five numbers: current customers, average revenue per user per month, monthly churn percentage, new customers gained per month, and expansion revenue from upsells. The tool instantly shows current MRR, annual run-rate, ARPU, and net new MRR, plus a twelve-month table that compounds churn and growth forward so you can see where the business lands in a year. Every calculation runs in your browser, so board-level numbers never leave your computer.

What This Tool Can Do

• Compute MRR from customer count multiplied by ARPU in real time.
• Show ARR as twelve times MRR for annual planning and investor updates.
• Echo ARPU back so mixed plans can be sanity-checked against the average.
• Compute net new MRR: revenue from new customers plus expansion minus revenue lost to churn.
• Project customers and MRR month by month for twelve months with compounding churn.
• Include expansion revenue so upsells and cross-sells show up in the forecast.
• Handle edge cases gracefully: zero customers, zero churn, or negative net growth all render sensibly.
• Work fully offline after load with no signup and no data collection.

Why MRR Matters and Who Needs It

Revenue is a lagging story, but MRR is the current chapter. Two companies with the same lifetime revenue can be in completely different shape if one grows net new MRR every month while the other bleeds churn. Tracking MRR, net new MRR, and the churn behind them tells you whether growth comes from selling more or merely from raising prices on a shrinking base.

• Founders preparing investor updates, pricing tests, or hiring plans tied to revenue milestones.
• Indie hackers checking whether a side project covers its costs and when it reaches ramen profitability.
• Marketers translating signup targets into revenue outcomes for campaign planning.
• Finance helpers and accountants who need a quick ARR sanity check before a deeper spreadsheet.
• Students learning subscription metrics for the first time with concrete numbers.

How the Maths Works

The core formulas are deliberately standard so the results match your accounting tool. MRR equals paying customers multiplied by average revenue per user. ARR equals MRR multiplied by twelve. Monthly churned customers equal customers multiplied by the churn rate, and churned MRR is that headcount times ARPU. Net new MRR equals new-customer MRR plus expansion MRR minus churned MRR. Each projected month applies churn to the starting base, adds the fixed number of new customers, rounds to whole people, and adds one more month of expansion revenue. Growth compounds because a bigger base churns more people in absolute terms even at a constant rate, which is exactly the treadmill subscription businesses feel.

How to Use This Tool

1. Type your current paying customers, counting only accounts that pay a recurring fee. Exclude free trials and cancelled accounts.
2. Type your ARPU per month in dollars. If plans differ, use total subscription revenue divided by paying customers.
3. Type your monthly logo churn percentage, for example 5 for five percent. Use customer churn here, not revenue churn, for the headcount model.
4. Type the new customers per month you realistically add, based on recent sales averages rather than hopes.
5. Type monthly expansion revenue from upsells and cross-sells, or leave zero when upsells are rare.
6. Read the summary cards: MRR, ARR, ARPU, net new MRR, and the twelve-month landing point.
7. Scan the projection table for the month you cross a target such as ten thousand dollars of MRR.
8. Play with the inputs: halve churn, double signups, or raise ARPU ten percent, and watch which lever moves the twelve-month number most.

Limitations You Should Know

This is a planning model, not accounting software. It assumes churn and signups stay constant all year, while real businesses are seasonal and lumpy. It models logo churn on headcount, so heavy downgrades or upgrades within the base show up only through the ARPU and expansion inputs rather than per-plan migration. Annual prepayments are smoothed into monthly equivalents, which matches MRR convention but differs from cash in the bank. Currency is shown in dollars with whole-number rounding for readability, so very small or foreign-currency businesses should treat the symbols as placeholders. For audited financials, always reconcile against your billing system rather than this estimate.

What to Do and What Not to Do

Do use honest trailing averages for churn and signups, ideally the last three months, because forecasts inherit every optimism in the inputs. Do separate expansion revenue from new-logo revenue so you can see which engine actually drives growth. Do revisit the projection monthly with fresh numbers instead of trusting a year-old forecast. Do compare scenarios side by side by noting down the twelve-month figure for each lever you test.

Do not count one-time setup fees or service income in MRR, since that inflates the recurring story investors will discount. Do not enter revenue churn into a logo churn field, or the headcount projection will drift. Do not assume a falling customer count with rising MRR is healthy without checking: it usually means price rises masking a leaky bucket. Do not share screenshots containing real customer counts publicly if that data is commercially sensitive.

Frequently Asked Questions