What MRR measures
Monthly recurring revenue is the subscription revenue you can expect every month, normalised to a monthly amount. It leaves out one-off fees and setup charges, and it spreads annual plans across 12 months. A customer paying $480 a year counts as $40 of MRR, not $480 in the month they paid.
How this calculator counts it
- Plan MRR = customers × monthly price, with the annual share discounted. If 40% of a $49 plan pays annually at 17% off, that plan's effective price is about $45.67.
- ARR = MRR × 12.
- ARPU = MRR ÷ customers.
- Net new MRR = new MRR + expansion MRR − churned MRR. This is the number that tells you whether you are growing.
The projection prices new customers at today's ARPU and applies churn and expansion to the previous month's MRR.
Reading the projection
Growth with steady signups and steady churn always flattens out. When the customers you lose each month equal the ones you gain, you have hit a ceiling. The calculator tells you where it is: new customers per month ÷ churn rate. At 25 new customers a month and 3% churn, you level off near 833 customers. To raise the ceiling, either add more customers each month or keep more of them.
Annual plans and cash
Annual billing does not change MRR, but it brings cash in up front. The calculator shows roughly how much annual plans collect in advance, which matters for runway even though MRR spreads it out.
Where the numbers come from
Use real counts from your billing system where you can. For a pre-launch plan, start with the SaaS pricing calculator to see how many customers a target needs, then model the path here. Everything runs in your browser and nothing is saved or sent.