MRR Calculator

What is MRR? Monthly Recurring Revenue (MRR) is total predictable monthly subscription revenue — number of active subscribers multiplied by average monthly subscription value. Unlike one-time-purchase revenue that resets each month, MRR compounds: each new subscriber adds to a growing base. But churn works against you just as powerfully, silently eroding that base every month. This calculator projects your MRR over 12 months by modeling the interplay between new subscriber acquisition and monthly churn.

The projection shows month-by-month subscriber counts, new additions, churned losses, and resulting MRR. It reveals the critical insight that most subscription founders miss: with an 8% monthly churn rate, you need to add 8% new subscribers every month just to stay flat. Growth only happens when new additions exceed churn, and the gap between them determines your growth trajectory.

For subscription box brands and replenishment products, healthy monthly churn rates range from 5 to 10%. Below 5% is exceptional. Above 10% means you have a product-market fit or experience problem that needs addressing before you scale acquisition. The most common causes of subscription churn are unexpected charges, product fatigue, shipping issues, and customers feeling locked in rather than delighted.

The most effective MRR growth strategies combine reducing churn (the most capital-efficient growth lever) with increasing new subscriber acquisition and expanding revenue per subscriber through upsells and plan upgrades. A 2% reduction in monthly churn often has a larger 12-month MRR impact than a 20% increase in new subscriber acquisition, because churn compounds against you while acquisition is linear.