Customer Retention Rate Calculator

Customer retention rate, often shortened to CRR, measures how well your business holds on to the customers it already has over a set period. This calculator works it out using a clean, widely accepted formula: take the number of customers at the end of the period, subtract any new customers you acquired during it, then divide by the number of customers you had at the start, and turn the result into a percentage. You enter three numbers, your starting customer count, your ending count and the new customers gained, and the tool returns your retention rate along with the matching count of retained customers. Subscription businesses, SaaS companies, gyms, agencies, retailers with loyalty programmes and any operator with repeat buyers rely on retention rate because keeping a customer is almost always cheaper than winning a new one, and small gains in retention compound into large gains in revenue and lifetime value. A high CRR points to strong product fit, good service and sticky habits, while a falling rate is an early warning that churn is creeping up and worth investigating before it hurts cash flow. To use it well, pick a consistent period such as a month, quarter or year and stick to it so trends are comparable, and define a customer the same way each time, for example an active paying account rather than a free trial. Track CRR alongside churn, which is simply 100 minus your retention rate, and segment it by plan, cohort or channel to find where loyalty is strongest. Aim to improve onboarding, support and value delivery, then watch whether retention climbs over successive periods rather than fixating on any single month.

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89.6%
Customer retention rate
Customers retained430
Churn rate10.4%

CRR = (end - new) / start x 100. Estimate only, not financial or tax advice.

How it works

Retention rate takes your ending customer count, removes the new customers you acquired, then divides by your starting count and multiplies by 100. The retained figure is ending minus new. Churn is simply 100 minus the retention rate.

Worked example

Starting with 480 customers, ending with 520 and acquiring 90 new ones, retained customers are 520 minus 90, which is 430. Dividing 430 by 480 gives 89.6 percent retention, so churn is 10.4 percent.

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