Monthly Active Users
MAU.
The metric most commonly used to price CIAM platforms, counting unique users who authenticated in a calendar month (definitions vary by vendor).
MAU pricing is the most-questioned model in CIAM evaluation. The complaint: at consumer scale, MAU costs compound steeply, and the unit economics break for high-MAU low-revenue-per-user apps (consumer media, freemium services, social applications). The 2026 alternatives are flat-rate self-host (Keycloak, FusionAuth, Zitadel), per-organization pricing (WorkOS, SSOJet), and per-MAU pricing with generous free tiers (Cognito, WorkOS AuthKit, MojoAuth).
Go deeper: Freemium model optimization for B2B SaaS unpacks the unit economics that make per-MAU pricing painful at consumer scale.
Common questions
Do all CIAM vendors define MAU the same way?
What's the difference between MAU and registered users?
How does MAU pricing scale at high volume?