Churn
The rate at which paying customers stop paying you. The silent killer of SaaS.
Churn is the percentage of customers (or revenue) you lose in a given period. Logo churn counts customers; revenue churn counts dollars. A 5% monthly churn rate sounds small but compounds catastrophically — it means you lose 46% of your customer base annually. Indie founders often ignore churn until it starts blocking growth; by then it's usually a product-market-fit signal, not a customer-success problem. Sub-5% monthly churn is table stakes for consumer SaaS; sub-2% is good; sub-1% is enterprise-tier.
Related terms
MRR (Monthly Recurring Revenue)
The predictable monthly revenue from active subscriptions. The indie-founder scoreboard metric.
LTV (Lifetime Value)
The total revenue a customer generates before they churn. What you can spend to acquire them.
Retention
The percentage of customers who stick around. The inverse of churn, but usually tracked by cohort.