How to use the expansion MRR calculator
Expansion MRR counts only the monthly recurring revenue added by customers who were already paying when the month began, through plan upgrades, extra seats or add-ons. MRR from customers who signed up this month is not expansion; it goes in its own field, is added to ending MRR, and is deliberately left out of NRR and GRR.
Net expansion MRR subtracts downgrades and churned MRR from expansion MRR, so it can be negative. Net revenue retention (NRR) adds net expansion to starting MRR and divides by starting MRR, which is why it can exceed 100% when upsell outweighs losses. Gross revenue retention (GRR) ignores upsell and cross-sell entirely and therefore can never exceed 100%.
Reading the two together separates where growth comes from. A low GRR with a high NRR means the business leans on a shrinking set of accounts spending more, so growth stalls the moment upsell room runs out.
Frequently asked questions
No. Expansion MRR measures only what existing customers added, so mixing in new customers inflates NRR and hides how well the existing base is actually holding.
Only treat a change as a downgrade when the recurring amount itself drops. A discount applied for a single month or a one-time refund is a one-off item, not an MRR movement.