Whether OpencellID API is free or chargeable

I am using OpencellID api in my .net application to get the Longitude and Latitude values.But i am able to use this API only 50 times per day.After that i am not getting the required data.

Note: Whether “Access Token” and “API Key” both are same or different in OpencellID API.


Same issue here, same question (note) also.

where from