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Churn Rate Calculator

Customer and revenue churn, with net churn after expansion. The two measures often disagree, and net revenue churn below zero is the state that lets a subscription business grow without acquiring anyone.

Also called: customer churn calculator, monthly churn percentage.

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Churn rate
3%

3% churn implies an average customer lifetime of about 33.33 months, and 30.62% a year if the rate holds. Enter revenue figures to see revenue churn, which often disagrees with customer churn. Enter expansion revenue to see net churn, which is what decides whether the base grows on its own.

Implied customer lifetime
33.33
Annualised churn
30.62%
Retention rate
97%
Revenue churn
0%
Net revenue churn after expansion
0%
Net customer growth
-3%
Customers at the end
970
On revenue against customer churn
Enter revenue figures to see revenue churn, which often disagrees with customer churn.
On net negative churn
Enter expansion revenue to see net churn, which is what decides whether the base grows on its own.
How this is calculated
Method and background

How this is calculated

Customer churn is customers lost over customers at the start. Revenue churn weights that by what each customer was worth, which is why the two disagree: losing thirty small accounts and losing three large ones can be the same revenue and very different customer churn. Expansion revenue from customers who upgrade offsets the loss, and when it exceeds it the net figure goes negative, meaning the existing base grows on its own. Lifetime is the reciprocal of churn, so the difference between two and three percent monthly is a lifetime of fifty months against thirty-three.

lifetime is the reciprocal of churn, so small changes at low churn move it enormously
c
Churn rate

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

three percent monthly churn

Customers at the start
1,000
Customers lost in the period
30
Customers added in the period
0
Revenue at the start
$0.00
Revenue lost to churn
$0.00
Expansion revenue from existing customers
$0.00

Churn rate3%

lifetime is the reciprocal of churn, 1/0.03

Open this example

expansion turns net churn negative

Customers at the start
1,000
Customers lost in the period
30
Customers added in the period
40
Revenue at the start
$5,000,000.00
Revenue lost to churn
$120,000.00
Expansion revenue from existing customers
$200,000.00

Churn rate3%

boundary: expansion exceeds the revenue lost, so the base grows on its own

Open this example

Method and limits

What it assumes

  • A constant churn rate, which real cohorts do not have: churn is highest early and flattens.

What it deliberately does not model

  • The reciprocal lifetime assumes constant churn, which overstates for a cohort whose curve flattens.
  • Short periods make churn noisy, and annualising a noisy monthly figure compounds the noise.
  • Customer and revenue churn can point in opposite directions, so reporting one alone is incomplete.

Formula version 1.0.0 · definition 1.0.0 · United States · Report a problem with this calculator

Frequently asked questions

Why do my customer and revenue churn differ?
Because revenue churn weights each loss by what the customer was worth. Losing many small accounts looks bad on customer churn and mild on revenue, and losing one large account is the reverse.
What is net negative churn?
Expansion revenue from existing customers exceeding the revenue lost to churn. The base grows without acquiring anyone, which is the strongest position a subscription business can be in.