DAU and MAU are the two headline active-user counts, and they differ only in the window. [[dau]] (Daily Active Users) counts the unique users who opened the app on a given day; [[mau]] (Monthly Active Users) counts the unique users who opened it across a ~30-day window. In both, a user is counted once per window no matter how many times they returned — these are reach metrics, not session counts.
The same product reports both, and the revealing number is the ratio between them. DAU divided by MAU is the [[dau-mau]] stickiness ratio: of all the people who used the app this month, what share use it on an average day? A ratio of 0.2 means the typical monthly user shows up roughly 6 days a month; 0.5+ is daily-habit territory.
DAU vs MAU at a glance
| DAU | MAU | |
|---|---|---|
| Window | A single day | A ~30-day rolling (or calendar) month |
| Measures | Daily reach / habit intensity | Total monthly reach / audience size |
| Volatile? | Yes — swings with weekday, campaigns, content | No — smooths daily noise |
| Best for | High-frequency apps (social, games, messaging) | Low-frequency apps (travel, finance, utilities) |
Neither is "better" — they answer different questions. DAU is about daily habit; MAU is about total reach. The ratio of the two is about stickiness.
Which one should you headline?
Match the metric to your usage frequency. A messaging app or a daily game lives or dies on DAU — if people do not open it most days the product is not working, and MAU would flatter a failing habit. A travel-booking app, a tax app, or an insurance app is naturally low-frequency: nobody books flights daily, so MAU is the honest reach number and a low DAU/MAU ratio is expected, not a problem.
The cardinal rule for both: watch your own trend, not the absolute number or a competitor's. Absolute DAU and MAU depend heavily on category, audience size, and ad spend, so cross-app comparisons mislead. A 5% month-over-month decline in your own DAU series is far more informative than how your number stacks against someone else's.
The 28-day vs calendar-month subtlety
"Monthly" is ambiguous. Calendar-month MAU varies with month length (28-31 days) and weekday alignment, injecting noise that has nothing to do with your product. Trailing-28-day MAU — every data point covering exactly 28 days — is the cleaner, more comparable definition, and it is what mature analytics teams use as the MAU denominator in the stickiness ratio. Most platforms (Amplitude, Mixpanel) expose both; pick one and stay consistent.