Retention Rate Calculator
Calculate customer retention rate. Enter your customer counts at the start and end of a period, plus any new customers gained, to get an instant percentage.
Recommended Settings
Pro Tips
- •Retention rate measures the percentage of existing customers you kept, excluding new customers acquired during the period
- •Retention rate and churn rate should add up to 100% when measuring the same customer base over the same period
- •A retention rate above 100% isn't possible with this formula, but revenue-based retention can exceed 100% through expansion revenue
- •Track retention rate by cohort (customers who joined in the same period) for more precise insight into customer behavior over time
Most Popular
Most users calculate retention rate monthly or annually alongside churn rate for a complete picture
When to Use This Tool
Measure what percentage of your existing customer base you successfully retained.
Report retention performance to leadership or as part of customer success KPIs.
Compare retention rates across different customer cohorts or acquisition channels.
Evaluate whether retention initiatives are improving customer stickiness over time.
How It Works
Subtract new customers acquired during the period from your ending customer count, isolating how many existing customers remained
Divide that number by your starting customer count
Multiply the result by 100 to express it as a percentage
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Frequently Asked Questions
Why do I need to subtract new customers?
Without removing new customers, growth from new acquisitions could mask churn among existing customers, making retention look artificially high. Subtracting new customers isolates how many of your original customers actually stayed.
How does this relate to churn rate?
Retention rate and churn rate are complementary - if you retained 92% of customers, you churned the other 8%. Calculating both gives you a complete picture.
Is my data sent to a server?
No. All calculations happen instantly in your browser using JavaScript. Nothing you enter is transmitted anywhere.
Can retention rate be revenue-based instead of customer-based?
Yes - many SaaS companies track net revenue retention (NRR) instead, which accounts for expansion and contraction revenue rather than just customer counts. Use the separate Net Revenue Retention Calculator for that metric.