Customer Retention Rate Calculator
Find the share of customers you kept over a period — retention and churn — excluding new sign-ups from the count.
How it works
Retention % = (customers at end − new acquired) ÷ customers at start × 100 · Churn % = 100 − retention
Retention rate measures how many existing customers you held onto, so it must strip out anyone acquired during the period — otherwise strong sign-ups would hide the customers quietly leaving. What remains, divided by the starting count, is the true retention rate; churn is simply its mirror image. Because keeping a customer is far cheaper than winning a new one, a few points of retention often move profit more than the same effort spent on acquisition.
Worked example
A business starts a quarter with 500 customers, ends with 520, and gained 80 new ones. Retained customers are 520 − 80 = 440, so retention is 440 ÷ 500 × 100 = 88% and churn is 12%.
Frequently asked questions
Why subtract new customers?
Retention is about the customers you already had. If you left new sign-ups in the end count, heavy acquisition could disguise heavy losses. Removing them isolates how well you kept the original base.
What is the difference between retention and churn?
They are two sides of the same coin: retention is the share who stayed, churn the share who left, and they always sum to 100%. An 88% retention rate is a 12% churn rate.
What is a good retention rate?
It depends on the model — subscription and SaaS businesses often target well above 90% annually, while some consumer categories naturally churn faster. Track the trend and compare to peers in your sector.
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Educational estimate, not financial or tax advice.