As per the notice just under 1 year ago, API Keys are now expected to be used by any application or service that makes regular use of the API.
Currently this restriction is simply imposed on calls which have a maxresults greater than 250 as we don’t currently have a method for counting ‘regular’ API use otherwise.
To get an API key, sign in to openchargemap.org and browse to ‘my profile > my apps’ and click register an application.
To use your API key include it as the value of the ‘X-API-Key’ header (case sensitive) or key= query string parameter (also case sensitive).
If this is not acceptable for any reason you can run your own API mirror system (or we can arrange for one to be hosted for you commercially). This is the same method we use for our own API load balancing: https://github.com/openchargemap/ocm-system/tree/master/API/OCM.Net/OCM.API.Worker