The API uses HTTP Basic authentication. The API key acts as the username. API keys are per-organization and can be generated and deleted in the Settings page. See our API Keys FAQ for more information.
Example cURL request with an api key.
curl "https://api.close.com/api/v1/me/" -u yourapikey:
Notice the ':' at the end of the api key. This is used because the key is sent as the username with a blank password.
API Base URL: