B2B ROI Calculator

Churn Rate Calculator

Customer & MRR churn (gross/net), annualized rate and lifetime. Benchmarks pre-filled, transparent formula, exportable report — free, no signup to calculate.

Advanced inputs & assumptions
How is this calculated?
  • churned = start + new − end · customerChurn% = churned / start × 100
  • monthlyRate = 1 − (1 − periodRate)^(1/n) (n = 1/3/12)
  • annualized% = (1 − (1 − monthlyRate)^12) × 100
  • gross MRR churn% = (churned + downgrade) / startMRR × 100
  • net MRR churn% = (churned + downgrade − expansion) / startMRR × 100
  • avg lifetime = 1 / monthlyRate (months)

Full methodology & benchmark sources →

Example with demo defaults — adjust to your numbers

Customer churn (period) 7.0%
Annualized churn 58.1%
Avg customer lifetime 15 mo
Gross MRR churn 3.5%
Net MRR churn 1.5%

Frequently asked questions

How is churn rate calculated?

Customer churn for the period is customers lost (start + new − end) divided by starting customers. We convert it to a monthly rate, annualize it, and derive average customer lifetime as 1 ÷ monthly rate. If you enter MRR figures, we also compute gross and net MRR churn.

What is the difference between gross and net MRR churn?

Gross MRR churn counts revenue lost to cancellations and downgrades. Net MRR churn subtracts expansion revenue from existing customers, so it can be negative — a negative net churn means your existing base is growing even before new sales (net revenue retention above 100%).

How do you annualize churn?

We convert your period rate to an equivalent monthly rate, then compound it over 12 months: annualized = 1 − (1 − monthlyRate)¹². This is more accurate than simply multiplying a monthly rate by 12, especially at higher churn.

Where do the default values come from?

The pre-filled numbers are demonstration defaults that produce a realistic example — they are not claimed industry averages. Replace them with your own figures for an accurate result. Where a field is labelled as an assumption, adjust it to match your business; the methodology page lists every default and its status.

Is my data stored anywhere?

No. Every calculation runs entirely in your browser. Nothing you type is sent to a server — there is no account and no copy of your numbers. If you download the PDF report, only the email you enter on the report form is stored, so we can follow up; your inputs stay on your device.