DAU
Daily Active User
The number of unique users who used a service or app on a given day.
In Simple Terms
DAU refers to the number of people who actually used an app or website on a specific day. Even if a service has a large number of registered members, that doesn't mean it's actively being used unless people are opening it regularly. That's why services like social media platforms and mobile games track DAU as a way to accurately measure how many people are really using them each day.
Behind the Name
DAU is short for the number of people who use a service on any given day. It comes from the initials of three English words: "Daily" (happening every day), "Active" (actively using it), and "User" (someone using the service).
Take a Closer Look!
DAU refers to the number of users (active users) who accessed and used an app or web service on a specific day.
Rather than counting the total number of registered accounts, it's a metric that counts the number of "unique users" (users identified by the service) who actually used it that day.
To put it simply, think of it like counting how many customers walk into a store each day.
The count is based on identifying information such as user IDs or devices, so if the same user opens the app multiple times in one day using the same account, it's still counted as just one. On the other hand, if the same person uses multiple accounts or devices, each one may be counted separately.
This metric excludes dormant users who are registered but not actually using the service, helping to reveal how much a service is genuinely used on a daily basis.
DAU is especially valued for services that are used repeatedly day after day, such as social media, mobile games, and news apps.
By tracking changes in DAU after launching a new feature or running a campaign, teams can objectively analyze how effective the initiative was and how users responded.
It's treated as key data for measuring how deeply a service has become part of people's daily lives, as well as the business's potential for future growth.