E-utilities usage policy limits the number of requests per second (rps) as follows:
Up to 3 rps: this is the default limit.
3 to 10 rps: permitted with an API key.
Exceeding 10 rps will result in throttling of requests with a corresponding 429 error code.
Above 10 rps: you may request an enhanced API key by writing to Help Desk with the following information:
- A general overview of the protocol/workflow you are using
- A set of example requests being sent to the server
- An approximate scale of the job (list the databases, and the number of records involved)
- Project duration (temporary or indefinite)
Note:
Third party applications, whether from a for profit or non-profit organizations, should allow individual users to supply their own key so that they are not required to share the bandwidth of the application. We only allow for reasonable rate adjustments, as the preferred method is to prioritize individual use over application or institutional use.
For specialized API services, review their documents and policies. You can use the API key that you obtain for E-utilities for Datasets APIs. You should use the enhanced API key (for above 10 rps) only for E-utilities.
