All free tools

calculate · free tool

Customer retention rate calculator

Measure retained and lost customers while catching impossible cohort inputs.

Private by default Immediate preview No signup for local exports

Live model

Customer retention rate calculator

Your inputs

Calculated locally
Enter a non-negative number.
Enter a non-negative number.
Enter a non-negative number.

Live results

Up to date
Retained customers
430
Customers lost
70
Retention rate
86%

Customer retention subtracts newly acquired customers from ending customers, then divides retained customers by the starting cohort.

How this tool works

A useful result, with clear limits

Separates retained customers from new customers in a cohort, then reports customer retention rate and losses.

How to use it

  1. Enter customers at period start and end.
  2. Enter new customers acquired during the period.
  3. Resolve any impossible cohort warning before using the percentage.

Inputs and output

Inputs
Starting customers, ending customers, and new customers acquired during the period.
Output
Retained customers, customers lost, and retention rate.

Formula

Retained = ending customers − new customers; retention rate = retained ÷ starting customers × 100.

Privacy

Cohort counts stay in local browser state and are not sent to a server.

Straightforward by design

What to expect

One focused workflow, clear constraints, and no hidden result gate.

Does Customer retention rate calculator upload my input?

The utility processes your input in this browser. ArcDemo only receives content when you explicitly choose a hosted save or product creation flow.