Why monthly active users (MAU) matter to a first-time founder
MAU shows how many distinct people receive enough value to perform an agreed action during a month. It helps founders separate a growing account list from actual product use. The number becomes misleading if “active” means merely opening an email or if the definition changes between reports.
Examples of monthly active users (MAU)
A budgeting app defines active as categorising at least one transaction. In April, 2,400 unique people log in, but only 1,500 categorise a transaction. Its April MAU is 1,500 under that definition. One person doing the action twenty times still counts once, not twenty times.
Common misunderstanding
MAU is not total registered users, monthly sessions or paying customers. It counts unique users meeting the activity rule during the period. A high figure can also hide weak retention if many new users replace those who leave, so founders should examine cohorts and repeat use alongside it.
When to use it
Use it for products where meaningful use naturally occurs at least monthly, and write down the qualifying action before tracking. Compare trends using the same definition. For a daily communication tool, daily active users may reveal more; for annual tax software, MAU may create noisy conclusions.