US Geological Survey · Rate Limits

Us Geological Survey Rate Limits

USGS does not publish a unified per-second/per-minute API rate-limit policy. The FDSN earthquake event service caps any individual query at 20,000 results (returning HTTP 400). Automated and high-volume consumers are explicitly directed to the real-time GeoJSON feeds rather than polling the query API. Endpoints that route through api.data.gov inherit its 1,000 req/hr per-key default.

2 Limits Throttle: 429
Federal GovernmentEarth ScienceRate Limiting

Limits

FDSN Event Query Result Cap query
results_per_query
20000
Queries that exceed 20,000 results return HTTP 400 Bad Request; page through the catalog or narrow time/space filters.
api.data.gov Fronted Endpoints key
requests_per_hour ยท hour
1000
Applies to USGS endpoints that authenticate via api.data.gov; see api.data.gov documentation.

Policies

Prefer Real-Time Feeds
USGS guidance is that automated applications should consume the real-time GeoJSON feeds rather than poll the query API for best performance and availability.
Bulk and Paging
Use the offset parameter and time/space filters to page through large result sets while staying under the 20,000-result query cap.
Operator Discretion
USGS reserves the ability to throttle abusive clients at the infrastructure layer; sustained high-rate scraping should be avoided.

Sources