Choose one period
Use one consistent period such as a month or quarter.Enter starting clients
Count clients active at the opening of that period.Enter ending clients
Count clients active at the close of the same period.Separate new clients
Enter clients first acquired during the period so they are not mistaken for retained starting clients.Review retention and churn
Retention shows the preserved starting cohort; churn is the complementary percentage of that starting cohort not retained.
Cold Plunge Client Retention Calculator
The Cold Plunge Client Retention Calculator measures the share of starting clients who remained active through the end of a selected period after removing clients acquired during that same period. It gives cold-plunge studios and recovery businesses a cleaner view of relationship continuity than simply comparing ending and starting headcount.
Use the retention rate alongside new-client growth and membership revenue. A stable client base can support scheduling and recurring revenue, while a falling rate may signal that onboarding, service consistency, pricing, or visit frequency deserves review.
Calculator inputs
clients
clients
clients
Result
—
client retention rate
Retained starting clients—
Starting clients not retained—
Period churn rate—
Net client change—
Retained clients = ending clients − new clientsRetention rate = retained clients ÷ starting clients × 100Churn rate = 100 − retention rate
Where:
- Starting clients — active client count at the beginning of the period.
- Ending clients — active client count at period end.
- New clients — clients acquired during the period.
- Retained clients — members of the starting cohort still active at period end.
Assumptions: The model assumes the three counts use the same definition of active client. It also assumes new clients are identifiable and are included in the ending count if still active.
What the result means
The percentage describes how much of the original client cohort remained active through the measurement period.
Retention does not explain why a client stayed or left; combine it with visit, cancellation, and membership data for diagnosis.
Given:
- 180 clients at the start
- 195 clients at the end
- 35 new clients during the month
Calculation:
Retained = 195 − 35 = 160. Retention = 160 ÷ 180 × 100 = 88.89%. Churn = 100% − 88.89% = 11.11%.
Result:
88.9% retention.
Interpretation:
About 89 of every 100 clients in the starting cohort were still active at month-end.
Why subtract new clients from ending clients?
New clients were not part of the starting cohort, so counting them as retained would inflate the rate. Subtracting them isolates clients who could actually have been retained.
Should I use visits, customers, or memberships?
Use one consistent entity. If the business primarily tracks memberships, use membership records; if it tracks individual clients regardless of plan, use unique clients.
What period should I measure?
Choose a period that matches the way customers buy and renew. Monthly reporting is common for monthly memberships, while quarterly views can reduce noise for less frequent services.
What if retained clients appear to exceed starting clients?
That usually indicates inconsistent definitions, reactivated clients, transfers, or a new-client count that does not capture every addition. Reconcile the cohort before using the rate.
How is retention different from net client growth?
Net growth compares total ending clients with starting clients. Retention follows only the starting cohort, so a business can grow overall while still losing many existing clients.