Monthly active user (MAU) is a key performance indicator (KPI) that measures how many users visited or interacted with a product or service.
The number of active users is a performance metric for the success of an internet product such as a social networking service, online game, or mobile app. It measures how many users visit or interact with the product or service over a given interval. This metric is commonly assessed per month as monthly active users (MAU), per week as weekly active users (WAU), or per day as daily active users (DAU).
Usually, a product user is considered "active" if they view the product or engage with the product during this interval. Examples of this type of product usage can include visiting the splash page of the product, commenting on a post on the product's social media page, and actually using the product itself.
Active users are calculated using the internal data of the specific company. Each company has their own method of determining their number of active users, and many companies do not share specific details regarding how they calculate them. Some companies make changes to their calculation method over time.