> For the complete documentation index, see [llms.txt](https://docs.layerlens.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.layerlens.ai/more-in-this-section-9/rate-limits.md).

# Rate limits

REST — rate limits and headers.

Per-API-key rate limits. Limits vary by tier and endpoint.

## Headers

* `X-RateLimit-Limit` — limit for the window
* `X-RateLimit-Remaining` — remaining
* `X-RateLimit-Reset` — when the window resets
* `Retry-After` (on 429) — seconds to wait

## Recommended

The SDK handles 429 + Retry-After automatically. For direct REST calls, check `Retry-After` and back off.

## See also

* [SDK: rate-limit handling](/more-in-this-section-9/rate-limit-handling.md)
* [Errors](/more-in-this-section-9/errors.md)