Known Limitations

API limitations

The Public Data API enforces certain limits to maintain performance, ensure stability, and prevent misuse.

---

API Rate Limiting

• The API allows up to 30 requests per minute (approximately 1 request every 2 seconds). If you exceed this limit, the API will return a 429 Too Many Requests error with the following response:

  {
      "error_key": "throttled",
      "error_message": "Too Many Requests"
  }
  

• Downloads of historic files via the API and WebUI are limited to 1,000 files at a time.

---

Geographic Rate Limiting

For security reasons, certain regions may be blocked from accessing *.ercot.com sites. Currently, regions outside the United States of America are restricted.

---

Available Data Date Ranges

API data downloads are available starting from each product’s initial activation date within the Public Data API system. For a comprehensive list of activation dates by product, refer to the Release Notes.

Data prior to the initial activation date is accessible exclusively as historic file downloads and is retained for at least 7 years.

---