Churn rate calculator

How it works

Churn % = (customers at start + acquired − customers at end) ÷ customers at start

Losses are derived from the three counts rather than asked for directly, which matters: those numbers are usually taken from different reports, and a hand-entered churn figure that disagrees with them produces a page where the arithmetic does not hold. New customers are excluded from the denominator — churn measures whether the people you already had stayed, and folding in acquisitions lets fast growth hide a leaking bucket.

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Frequently asked questions

Why are new customers not in the denominator?

Because churn asks whether the base you started with stayed. Dividing by a base swollen with new arrivals produces a lower number that improves fastest when you grow fastest, which is exactly backwards.

Customer churn or revenue churn?

This is customer churn. Revenue churn weights each loss by what it was worth, and the two can point in opposite directions if the customers leaving are small or very large.

How do I annualise a monthly rate?

Not by multiplying by twelve. Annual retention is monthly retention to the twelfth power: 2% monthly churn is about 21.5% a year, not 24%.

What is an acceptable churn rate?

Depends on segment. Consumer subscriptions live with several percent a month; enterprise contracts measure it in low single digits a year. Compare with your own trend first.