The number of companies you are able to query in a 30-day period is subject to the terms of your partnership agreement with Craft.
Craft does not put restrictions on the number of API calls you are able to do in a 30-day period. However, we do recommend to not perform more than 10 requests per second to the Company Data API. The Company Data API speed varies from request to request, depending on the depth of data requested for the query.
All usage of the Craft Company Data API and other APIs are subject to the terms of your partnership agreement with Craft.