What is Monthly Active Users?
Monthly Active Users (MAU) counts unique users who engaged with your product at least once in the past 30 days. It's the standard measure of user base size and growth for consumer and SaaS products.
The definition of "active" matters. A login might count, but meaningful activity (creating content, completing tasks) is more valuable to track.
Why MAU Matters
MAU shows the size of your engaged user base. Growing MAU indicates product-market fit and successful acquisition. Declining MAU signals churn problems or market saturation.
MAU alone doesn't tell the whole story. A product with 1M MAU but 5% daily engagement differs dramatically from one with 100K MAU and 50% daily engagement.
MAU vs Other Metrics
Track MAU alongside DAU (daily engagement), WAU (weekly patterns), and retention cohorts (how MAU composition changes over time). Growing MAU from new users while losing old users is a warning sign.
Formula
MAU = Unique users with at least one session in the past 30 days
Define "active" based on meaningful actions, not just logins
Example
Your SaaS product tracks user activity:
- Total registered users: 50,000
- Users active in last 30 days: 12,000
MAU = 12,000
Activation Rate = 12,000 ÷ 50,000 = 24%
Only 24% of registered users are active. Focus on activating the dormant 76% or improving acquisition quality.