Web Service Rate Limits

Limits are placed on the number of Data.gov Web service requests you may make using your API key.

For each API key, these limits are applied across all Data.gov Web services requests. Exceeding these limits will lead to your API key being temporarily blocked from making further requests. Depending on the limit exceeded, the block will be lifted automatically by waiting until the next hour or calendar day.

Understanding Rate Limit Time Periods

Hourly Limit

The hourly counters for your API key reset on a rolling basis.

Example: If you made 500 requests at 10:15AM and 500 requests at 10:25AM, your API key would become temporarily blocked. This temporary block of your API key would cease at 11:15AM, at which point you could make 500 requests. At 11:25AM, you could then make another 500 requests.

Rate Limit Error Response

If your API key exceeds the rate limits, you will receive a response with an HTTP status code of 429 (Too Many Requests).

Need Higher Limits?

If you're building an application that needs higher rate limits, we'd be happy to work with you. Contact us for more details.