MAU (monthly active users)

How it works

Each person is counted once per month, however many times they open the app. Someone who opens it every day and someone who opens it once both add one to the total. The count resets each month, so a user who stops opening the app drops out of MAU even though the install still exists.

Definitions vary in two ways. "Active" can mean any app open or a specific action such as logging in. "User" can mean a device or a signed-in account, and one person with a phone and a tablet may count as two. When MAU sets your price, ask the vendor which definition its count uses.

When it matters

MAU matters for cost in two situations. The first is a plan priced by MAU tiers, where crossing a tier boundary raises the price in a step. The second is sizing a plan priced by another unit. Airbridge, for example, bills Core by data points and says its $40 base covers about 35,000 monthly active users at typical usage.^[1] A statement like that is a guide for sizing, and your own events per user decide the real figure.

MAU pricing suits an app that spends heavily on ads relative to its user base, because paid installs do not add cost one by one. It suits an app with a large, mostly organic audience less.

How it relates to attribution

MAU is a measure of audience size, and attribution reports are built on installs and events. The two meet in pricing and in ratios such as events per active user, which you need for estimating a monthly bill. For measuring how many users stay active after install, see retention. For how MAU compares with other pricing bases, see billing unit.