The Analytics API is only available on Premium plans and plans including the Enterprise add-on.
This is not a metered feature and users aren’t charged for using the feature.
Keeping in mind there is a rate limit of 100 API calls per minute per app in place as a security precaution to prevent overloading Algolia's infrastructure.
If your plan includes the analytics feature, you may use the api as much as you like within the rate limiting thresholds.