We are launching in public beta a new feature to throttle / rate limit API key usage per hour.

You can manage the feature from the Ipregistry dashboard:
https://dashboard.ipregistry.co/keys

Please note the feature is in beta and is provided with no guarantees or SLA. Once enabled, its usage may also slightly reduce the API response time for the key you are using. Make sure to enable throttling only when it is really needed.