Authentication
HubSpot API key is used in every request made for authenticating the API calls.
Each key is specific to a HubSpot account, not an individual user.
Only one key is allowed at a time. You can deactivate your API key and generate a new one at any time.
Currently, there is no mention of HubSpot API keys expiring in the HubSpot documentation.
API Limits
40,000 API calls per day (without the API add-on)
Up to 160,000 API calls per day (only with the API add-on)
10 requests per second API rate limit
Requirements
API access to the following Hubspot tables:
Contacts
Companies
Campaigns
Email events
Email subscription activity
Forms
API write access to these standard objects:
Contacts Object: The batch API can update 1000 records in per API call. So, an update of 100K records needs ~100 API calls.
Company Object: The batch API can update 100 records in per API call. So, an update of 100K records requires ~1000 API calls.
Data dictionary and custom business rules to describe lead scoring and workflow in HubSpot.