Customer Retention Rate Calculator
Calculate customer retention rate from customers at the start and end of a period and new customers acquired — plus churn and customers retained.
How it works
Retention rate % = ((customers at end − new customers acquired) ÷ customers at start) × 100 · Churn % = 100 − retention %
Customer retention rate measures the share of existing customers you keep over a period. The key is to strip out customers acquired during the period, so growth from new sales does not disguise losses among the customers you already had: subtract new customers from the ending count, divide by the starting count, and multiply by 100. Retention and churn are two sides of the same coin — they always sum to 100%. Retention is one of the most powerful levers in a business because keeping an existing customer is far cheaper than acquiring a new one, and small improvements compound: a few points of higher retention lift lifetime value and let acquisition spending build the base rather than just replace losses.
Worked example
A business that started with 500 customers, ended with 470, and acquired 40 new ones during the period retained 470 − 40 = 430 of the original group. Retention is 430 ÷ 500 × 100 = 86%, so churn is 100 − 86 = 14%.
Frequently asked questions
Why subtract new customers when calculating retention?
Retention should measure how well you keep the customers you already had, not how many new ones you won. If you counted new customers, strong acquisition could hide serious losses among existing customers. Subtracting them isolates the true retention of the starting base.
What is a good customer retention rate?
It varies widely by industry and business model. Subscription and SaaS businesses often target annual retention well above 85–90%, while some consumer categories naturally see lower repeat rates. Track your own trend over consistent periods rather than chasing a universal benchmark.
How is retention rate related to churn?
They are complements: retention rate + churn rate = 100%. If you retain 86% of customers, you churned 14%. Retention frames the number positively (customers kept); churn frames it as customers lost. Both describe the same underlying movement in your customer base.
Related calculators
Educational estimate, not financial advice.