Source: https://databento.com/docs/api-reference-data/basics/rate-limits


### Rate limits

Our reference API allows each IP address up to:
- 100 concurrent connections.
- 100 [corporate actions](https://databento.com/docs/api-reference-data/corporate-actions.md) requests per second.
- 100 [adjustment factors](https://databento.com/docs/api-reference-data/adjustment-factors.md) requests per second.
- 100 [security master](https://databento.com/docs/api-reference-data/security-master.md) requests per second.

When a request exceeds a rate limit, a `BentoClientError` exception is raised
with a 429 error code.

**Retry-After**

The Retry-After response header indicates how long the user should wait before retrying.

If you find that your application has been rate-limited, you can retry after waiting for the time specified in the Retry-After header.

If you are using Python, you may use the time.sleep function as seen below to wait for the time specified in the Retry-After header.
e.g. `time.sleep(int(response.headers("Retry-After", 1)))`

This code snippet works best for our current APIs with their rate limits. Future APIs may have different rate limits, and might require a different default time delay.