Net MRR Churn Calculator Formula

Understand the math behind the net mrr churn calculator. Each variable explained with a worked example.

Formulas Used

Net MRR Churn

net_mrr_churn = churned_mrr + contraction_mrr - expansion_mrr

Net MRR Churn Rate

net_mrr_churn_rate = starting_mrr > 0 ? ((churned_mrr + contraction_mrr - expansion_mrr) / starting_mrr) * 100 : 0

Negative Churn?

is_negative_churn = (churned_mrr + contraction_mrr - expansion_mrr) < 0 ? 1 : 0

Variables

VariableDescriptionDefault
churned_mrrChurned MRR (cancellations)(USD)10000
contraction_mrrContraction MRR (downgrades)(USD)3000
expansion_mrrExpansion MRR (upgrades & add-ons)(USD)15000
starting_mrrStarting MRR(USD)200000

How It Works

How to Calculate Net MRR Churn

Formula

Net MRR Churn = Churned MRR + Contraction MRR - Expansion MRR Net MRR Churn Rate = Net MRR Churn / Starting MRR x 100

Net MRR churn is the ultimate SaaS retention metric because it captures both the revenue you lose and the revenue you grow from existing customers in a single number. When expansion exceeds losses, you achieve net negative churn, meaning your existing customer base generates more revenue over time even without new sales. This is the most powerful growth engine a SaaS company can build.

Worked Example

Starting MRR is $200,000. Cancellations lost $10,000, downgrades lost $3,000, but expansions added $15,000.

churned_mrr = 10000contraction_mrr = 3000expansion_mrr = 15000starting_mrr = 200000
  1. 01Net MRR Churn = $10,000 + $3,000 - $15,000 = -$2,000
  2. 02Net MRR Churn Rate = (-$2,000 / $200,000) x 100 = -1%
  3. 03Negative churn of -1% means existing customers grew by $2,000 net.

Ready to run the numbers?

Open Net MRR Churn Calculator