Monthly Recurring Revenue Calculator

MRR (Monthly Recurring Revenue) is the predictable monthly income from subscription clients. For SaaS, service businesses, and retainer-based freelancers, MRR growth is the key metric. This calculator shows current MRR, annual recurring revenue, and projects year-end based on churn and new client acquisition.

20 clients at 200 monthly = 4,000 MRR, 48,000 ARR. With 5% monthly churn (1 client lost monthly) and 2 new clients monthly, annual net is +12 clients, ending at 32 clients and 6,400 MRR - 60% growth over the year.

Churn and new client rates matter more than people realise. Same starting MRR with 10% churn (2 lost monthly) vs 2 new = net zero growth. Small changes in either rate compound into large MRR differences over time.

Quick example

With current client count of 20 and average monthly fee of 200 (plus monthly churn rate of 5% and new clients per month of 2), the result is 4,000.00. Change any figure and watch the output shift — it's often more useful to see the pattern than to memorise the formula.

Which inputs matter most

You enter Current Client Count, Average Monthly Fee, Monthly Churn Rate, and New Clients per Month.

What's happening under the hood

Current MRR = clients × fee. ARR = MRR × 12. Annual churn = clients × churn × 12. Net new = new clients × 12 - churn. Year-end MRR = (clients + net new) × fee. The formula is listed in full below. If the number looks off, you can retrace the calculation by hand — that's the point of showing the working.

Worked example with realistic numbers

Imagine a freelancer offering ongoing design retainers. They have 15 clients paying 500 per month each, giving current MRR of 7,500. They lose clients at 8% per month (roughly 1 client) and typically sign 3 new clients each month.

• Current MRR: 15 × 500 = 7,500
• Annual recurring revenue: 7,500 × 12 = 90,000
• Annual churn: 15 × 0.08 × 12 = 14.4 clients lost
• Annual new clients: 3 × 12 = 36 clients gained
• Net change: 36 − 14.4 = +21.6 clients
• Year-end client count: 15 + 21.6 = 36.6 clients
• Year-end MRR: 36.6 × 500 = 18,300

This models 144% growth in monthly recurring revenue over twelve months, showing how acquisition and churn rates interact.

When this metric matters

MRR and ARR are relevant for any revenue stream with recurring client relationships or subscription elements. They help illustrate:

• Baseline revenue stability and predictability month to month
• The compounding effect of client losses and gains over time
• Which variable (churn rate or new client acquisition) has stronger impact on year-end revenue
• The gap between current and projected revenue without intervention

What this calculation captures and what it does not

This tool models revenue flow assuming constant monthly fee, churn rate, and new client acquisition throughout the year. It illustrates linear compound growth.

The calculation does not account for:

• Fee increases or pricing changes during the year
• Seasonal variation in churn or new client sign-ups
• One-off revenue (project work, consulting fees, refunds)
• Client lifetime value or profitability
• Time lag between signing a client and revenue recognition
• Operating costs or margins

The result is for educational illustration and pattern recognition, not operational forecasting.