About

Customer retention is the lifeline of any subscription-based business. High acquisition rates are meaningless if the "bucket is leaking" at the bottom. This calculator helps business owners and product managers quantify their customer attrition. By tracking how many customers leave over a specific period relative to the starting count, businesses can identify trends before they become critical failures. Monitoring these metrics monthly allows for agile responses to product dissatisfaction or competitive pressure.

Formulas

The core metrics are derived from the flow of customers during a period t.

C_lost = (C_start + C_new) − C_end

Churn Rate = C_lostC_start × 100

Projected Annual Loss = C_start × (1 − (1 − rate)¹²)

Reference Data

Metric	Formula Structure	Target Benchmark (SaaS)	Impact
Churn Rate (Monthly)	LostStart × 100	3% - 5% (B2C)	Revenue Drag
Retention Rate	100% − Churn Rate	> 95%	Stability
Annualized Churn	1 − (1 − Rate)¹²	5% - 7% (Enterprise)	Long-term Viability
Customer Lifetime	1Churn Rate	20+ Months	LTV Calculation
Revenue Churn	(Lost MRR / Start MRR) × 100	Negative (Net Negative)	Expansion Revenue
Logo Churn	Count Based	Varies	Market Share

Frequently Asked Questions

Gross Churn measures the percentage of revenue or customers lost without accounting for any new sales or expansion revenue. Net Churn accounts for expansion revenue (upsells/cross-sells) from existing customers. Net Churn can be negative (which is good), while Gross Churn is always 0 or positive.

Dividing by the end count distorts the data because the end count is influenced by new growth. The standard method is to divide lost customers by the number of customers present at the start of the period to see what portion of the original cohort left.

For B2B Enterprise SaaS, 5-7% annual churn is excellent. For B2C subscriptions (like Spotify or Netflix), monthly churn rates around 3-5% are common due to lower switching costs.

This tool calculates "Logo Churn" (customer count). It does not account for revenue churn (MRR) caused by downgrades. For financial accuracy, you should track MRR Churn separately.