The math, shown
Churn rate is the share of your customers who cancelled during a period. This calculator measures customer churn, month by month.
Churn rate = customers lost ÷ customers at the start of the month
Customers at the start of the month
Paying customers on the first day of the month.
Customers lost during the month
Customers from that starting group who cancelled during the month. Customers who joined during the month are not counted in either number.
Worked example
Suppose you started the month with 500 customers and 15 of them cancelled.
15 ÷ 500 = 0.03, or 3% monthly churn.
The chart applies that rate to 500 customers for 12 months. At 3% a month, about 347 would remain after a year, which is a loss of about 31%. A small monthly rate adds up quickly.
How to read your result
Churn compounds, so compare it as a monthly rate and also as a yearly loss. Annual loss is 1 − (1 − monthly churn)12: about 22% at 2% monthly, 31% at 3%, 46% at 5% and 58% at 7%.
David Skok writes that if net revenue churn is above 2% a month, you are losing about 22% of your revenue every year. That is revenue churn, which differs from customer churn, so it is a guide and not a direct benchmark for this calculator. One 2025 summary of industry reports (Orb, citing Vena) puts SMB-focused SaaS at 3% to 7% monthly churn. We have not checked the original report, so treat that range as indicative. Compare yourself with businesses like yours and watch your own trend.
Frequently asked questions
What is the difference between customer churn and revenue churn?
Customer churn counts the customers who left. Revenue churn counts the recurring revenue they took with them. If your biggest customers leave, revenue churn is higher than customer churn, and the reverse if small ones leave. This calculator shows customer churn.
Which period should I enter?
Enter figures for one month so the result is a monthly rate. The chart and the yearly figures assume the rate repeats every month. If you enter a quarter or a year, the result is the churn for that period, and the chart will be wrong.
Is low churn always a good sign?
Not on its own. With few customers, one cancellation moves the rate a lot. Churn can also be low overall and high in one plan or customer group. Look at several months and at your biggest groups of customers.
Sources
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Written by the Webtilly team
Note: This calculator provides an estimate based on the formula shown above. It is not tax, legal, or financial advice.