A monthly active user (MAU) is a unique user who performs at least one qualifying action in an app or website within a 30-day or calendar-month period.
What is a Monthly Active User (MAU)?
MAU is typically scoped as either a rolling 28- or 30-day window or a fixed calendar month, and many teams prefer 28 days because it contains the same number of weekends each period, avoiding a bias from month length. Because the window is long, MAU is stable and resistant to distortion from a single campaign or event, which is why vendors and investors often use it as the headline growth figure and why some pricing models bill per MAU. Teams commonly pair MAU with Daily Active User (DAU) and Weekly Active User (WAU) rather than reporting it alone, since a long window that is good for stability is also slow to reveal a problem developing inside it. One frequent variant is defining the qualifying action more strictly than "any app open," for example requiring a purchase or a social action, which produces a smaller but more meaningful figure for engagement-focused reporting.
Why Monthly Active Users Matter
MAU answers the question "how many people actually use this product" in a way that install counts and registered accounts cannot. Leadership uses it to track growth quarter over quarter, finance uses it to model revenue per user and to size vendor contracts that bill per MAU, and marketing uses it to judge whether acquisition spend produced users who stayed past the first session. Because the window is long, MAU is stable and hard to distort with a single campaign, which is exactly why it is trusted externally. The same stability is its weakness internally: MAU is slow to reveal a problem, so product teams pair it with DAU and WAU for early signals.
How to Calculate Monthly Active Users
MAU is a deduplicated count over the chosen window. The definition of an active action should match the one used for DAU and WAU so the three metrics can be compared.
| Element | Options | Notes |
|---|---|---|
| Window type | Calendar month or rolling 28 or 30 days | 28-day windows contain the same number of weekends each period |
| Qualifying action | App open, login, or a meaningful action such as posting or purchasing | Choose one definition and keep it fixed |
| Deduplication | One count per user per window | 20 sessions in a month = 1 MAU |
| Companion ratios | DAU/MAU for stickiness, WAU/MAU for weekly reach | Ratios give MAU its meaning |
Worked example: in a 30-day window an app records 150,000 unique users who completed at least one qualifying action. The same period averages 30,000 DAU. DAU/MAU is 30,000 divided by 150,000, or a 20% user stickiness ratio, so the average user opens the app on about six days out of thirty. If MAU grows to 180,000 next month while DAU stays at 30,000, the ratio drops to 16.7%. The audience got bigger but less engaged, a pattern that often follows a paid acquisition push, and one the raw MAU figure alone would hide.
MAU also anchors monetization math. Revenue divided by MAU gives average revenue per user, and for products with in-app purchases or subscriptions, tracking that figure alongside MAU shows whether growth is bringing in paying users or only browsers.
Monthly Active Users and social.plus
Growing MAU while holding engagement steady requires infrastructure that scales with the audience. social.plus provides engagement infrastructure, including feeds, chat, groups, live streaming, stories, and profiles, delivered through SDKs, APIs, and UIKit, for consumer apps that operate at large scale. Noom runs community features for 45M+ users, and Betgames delivers interactive experiences to 200M users. Brands using social.plus features report engagement rates of 20-50% and retention lifts of 10-35%, which is what keeps the DAU/MAU ratio healthy as the monthly audience grows.
Key Takeaways
- A monthly active user is a unique person who performs a qualifying action within a 30-day or calendar-month window.
- MAU measures audience size and is the standard figure for growth reporting and per-user pricing, but it is slow to reveal problems.
- DAU/MAU turns MAU into an engagement measure; a growing MAU with a falling ratio means the audience is expanding faster than habit.
- Use the same definition of "active" across DAU, WAU, and MAU so the three can be compared.