How the retention formulas work
Logo churn divides customers lost during the period by customers present at the start. Gross revenue retention subtracts churned and contracted MRR from starting MRR. Net revenue retention then adds expansion from that same starting cohort. New-customer MRR is excluded because retention asks what happened to customers you already had.
Use one consistent period, currency, customer scope, and subscription policy. Annual contracts should be normalized, and one-time revenue should remain outside MRR.
Why customer churn and revenue churn diverge
Losing five small customers can create high logo churn but little revenue churn. Losing one enterprise account can produce the opposite result. Review both measures, then segment retention by plan, acquisition channel, customer size, and cohort age.
Read projections as sensitivity analysis
The projection compounds the entered monthly rates. It does not add new customers or assume that churn remains stable forever. Use it to understand the cost of a retention problem, then replace the constant-rate model with actual cohort curves when enough history exists.