DAU(Daily Active Users)
The number of unique users who were active in your app or product on a given day.
Definition
DAU (daily active users) counts the distinct people who used your product during one day. As with monthly active users, you decide what "active" means: an app open, a session, or a meaningful action such as completing a lesson or sending a message. DAU is the main health metric for products meant to be used every day, such as social apps, messaging, games, fitness and language learning.
Why It Matters
DAU shows habit. A product can have a large monthly audience that only checks in occasionally, or a smaller one that comes back every day; DAU tells them apart, especially as the DAU/MAU ratio. Daily data also reacts quickly to releases, outages, campaigns and push notifications, which makes DAU the first place teams look when something changes. Pushing DAU up with notifications that annoy users, though, often lowers it later as people opt out or uninstall.
How It Works
Count unique user or device IDs that performed the active action within a calendar day, using a consistent time zone. Average DAU over a week or month to remove weekday swings, and divide average DAU by MAU to get the stickiness ratio. Break DAU down by platform, cohort and acquisition source, and compare it with retention curves to see whether daily usage comes from new users or long-term ones.
Example
A language-learning app tracks its numbers in March:
- Average DAU: 410,000 learners who completed at least one lesson.
- MAU: 1,150,000.
- DAU/MAU: 36%, meaning the average monthly learner practices about 11 days a month.
After adding a streak reminder at each user's usual practice time, DAU rises to 432,000 while push opt-outs stay flat, so the team keeps it.
Best Practices
- 1Use the same definition of active for DAU and MAU so the ratio means something
- 2Report weekly averages of DAU rather than single days
- 3Track DAU by cohort to separate new-user spikes from lasting habits
- 4Watch opt-outs and uninstalls when you use push to raise DAU
- 5Pick DAU as a north-star metric only if your product is meant for daily use
DAU/MAU Ratio Reference
These estimates use mean DAU across the same 30-day month divided by that month's MAU. A single day's DAU/MAU ratio does not determine average active days. App categories are illustrative examples, not benchmarks.
| DAU/MAU | Average active days per month | Illustrative app category |
|---|---|---|
| 10% | About 3 | Occasional-use apps like travel |
| 20% | About 6 | Many consumer and productivity apps |
| 50% or more | About 15 or more | Messaging, social, daily games |