# Usage and limits

For Headless APIs, the usage is based on MAUs (Monthly Active Users). \
\
MAU is the number of unique users (with uniqueness defined by the user-ID) that create or consume content on Circle servers through SDK or API within a monthly billing cycle. All service requests except authentication\* are counted as MAU. MAU number is based on per-user instead of per-device, meaning that a user with the same user-ID with multiple devices will be counted as 1 MAU.

### Exceptions

Authentication endpoints are not taken into account, so you can use them without increasing your MAU count. Here's a list of what we consider Auth endpoints:

* /api/v1/headless/access\_token/refresh
* /api/v1/headless/access\_token/revoke
* /api/v1/headless/auth\_token
* /api/v1/headless/refresh\_token/revoke
* /api/headless/v1/cookies
* /session/cookies (cookies redirect URL)