Glossary
What is DAU (daily active users)?
Daily active users is the number of unique users who engage with a product on a single calendar day — the core short-cycle engagement metric.
What DAU is good for
DAU is the fastest feedback loop available. A release, an outage, a campaign or a seasonal effect shows up the same day, which makes it the right metric for operational monitoring.
It is a poor metric for judging health, because it moves for many reasons that have nothing to do with the product — day of week, marketing spend, holidays, a single viral moment — and a number that moves for many reasons explains none of them.
Reading it properly
- Compare like days. Weekly seasonality is strong in almost every product; Tuesday against Sunday is not a comparison.
- Read it against [MAU](/resources/glossary/monthly-active-users-mau) to get stickiness, which is far more informative than either alone.
- Separate new from returning. Rising DAU driven entirely by acquisition is a spend chart, not an engagement chart.
- Watch it against [retention](/resources/glossary/retention-rate) cohorts, which tell you whether today's users will still be here next month.
The trap
DAU can be bought. Increase acquisition spend and DAU rises regardless of whether the product improved, which makes it the easiest metric in the business to move and the least meaningful to move.
The diagnostic is simple: hold acquisition flat and see what DAU does. A product with genuine engagement holds; one whose DAU is a function of spend decays immediately. Teams that never run that check can spend years mistaking a marketing budget for product-market fit.
Common questions
What DAU/MAU ratio is good?
It depends entirely on the product's natural frequency. A messaging app should be high; a tax filing tool should not, and holding it to the same standard would be meaningless.
Should DAU include new users?
The headline usually does, and it should also be reported split. Otherwise a rise in acquisition is indistinguishable from a rise in engagement.
More in growth and engagement
Acquiring users, and the behaviour that says whether they stayed.