Churn Rate Calculator
Customer and revenue churn measured against the customers you started with, plus retention, average lifetime and what the same rate does over a year.
Customers at start of month 1,200
New customers 180
Customers lost 54
Customers at end 1,326
Customer churn rate 4.5%
Customer retention rate 95.5%
Net customer growth 10.5%
Average customer lifetime 22.2 months
Same rate over a year 42.5%
Revenue at start of month $48,000.00
Revenue lost to churn $2,400.00
Expansion revenue $1,500.00
Gross revenue churn 5%
Net revenue churn 1.88%
Net revenue retention 98.13%
Churn is measured against the 1,200 customers you started the month
with. The 180 you won during it are deliberately not in the denominator:
including them would report 3.91% instead of 4.5%, and the faster you
grow the better that made-up number would look.
Gross revenue churn of 5% against customer churn of 4.5% tells you the
size of the accounts leaving. Higher revenue churn than customer churn
means your larger customers are the ones going.
An average lifetime of 22.2 months is the reciprocal of the rate, which
assumes the rate holds. It rarely does: churn is highest in the first
weeks and falls after, so this overstates the risk for a settled cohort
and understates it for a new one.
Output is valid and updates as you type.
Fix the highlighted fields to update the output.
Churn is a division, and the whole argument is about the bottom of it. This divides the customers you lost by the customers you had at the start of the period, which is the definition, and it shows you what the flattering version would have said so you can tell them apart.
It also separates customer churn from revenue churn, because losing fifty small accounts and losing one large one are the same logo churn and two different problems.
How to use
- Put in the customers you had on the first day of the period.
- Put in the ones you won and the ones you lost during it.
- Pick the period. A monthly or quarterly rate is also compounded out to a year.
- If you want revenue churn too, fill in the recurring revenue you started with, what you lost, and any expansion from customers who stayed. Leave them at zero to skip that section.
Example
1,200 customers at the start of the month, 180 won, 54 lost, on 48,000 of recurring revenue with 2,400 lost and 1,500 of expansion:
Customers at start of month 1,200
New customers 180
Customers lost 54
Customers at end 1,326
Customer churn rate 4.5%
Customer retention rate 95.5%
Net customer growth 10.5%
Average customer lifetime 22.2 months
Same rate over a year 42.5%
Revenue at start of month $48,000.00
Revenue lost to churn $2,400.00
Expansion revenue $1,500.00
Gross revenue churn 5%
Net revenue churn 1.88%
Net revenue retention 98.13%The same month reported with the new customers in the denominator gives 3.91 percent. Nothing about the business changed; 54 customers still left. The number just got smaller because you had a good month for signups.
Pitfalls
New customers do not belong in the denominator. They were not there to churn. Putting them in makes the rate fall whenever growth rises, which is the exact moment you need the number to be honest, and it is the single most common way a churn figure gets quietly wrong.
A monthly rate does not multiply out to a year. Five percent a month is 46 percent a year, not 60, because each month churns what is left rather than what you started with. The annual line here compounds.
Average lifetime is a reciprocal, and it assumes the rate holds. Churn is highest in the first weeks and falls after, so one blended rate overstates the risk for a cohort that has already stuck around and understates it for one that just signed up. If the decision is expensive, split the cohorts.
Gross and net revenue churn answer different questions. Gross tells you what you lost. Net subtracts expansion and can go negative, which is what people mean by net revenue retention above 100 percent. Both are real; quoting only the net one hides how much you are losing.
Downgrades are churn too. A customer who cuts from twenty seats to two has not left, so they are not in the customer churn, but the revenue is gone and it belongs in the revenue lost field.
Compatibility
Arithmetic in the browser: nothing is uploaded and nothing is stored. The share link carries the figures, which is the easy way to send a board pack number with its workings attached.
The tool takes counts and totals rather than connecting to your billing system, which means it works the same whether you bill through Stripe, WooCommerce Subscriptions, Paddle or invoices in a spreadsheet. Pull the four counts from wherever your subscriptions actually live.
One definition worth fixing before you use any churn number: decide whether a customer churns on the day they cancel or on the day their paid period ends. Both are defensible, mixing them is not, and the second is usually what finance means.