> ## Documentation Index
> Fetch the complete documentation index at: https://signatureapi-daf4ee54.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Rate Limiting

> Understand API rate limits and how to handle throttled requests

SignatureAPI enforces rate limits to ensure fair usage and platform stability. Rate limits are applied per API key.

There are two components to rate limiting:

* **Rate** is the sustained number of requests allowed per second.
* **Burst** is the maximum number of requests that can be sent in a short spike before throttling kicks in. Once the burst is exhausted, requests are throttled to the sustained rate.

## Default limits

| Metric | Limit              |
| ------ | ------------------ |
| Rate   | 10 requests/second |
| Burst  | 10 requests        |

## Extended limits

For higher-volume workloads, the extended plan increases both limits:

| Metric | Limit                 |
| ------ | --------------------- |
| Rate   | 1,000 requests/second |
| Burst  | 1,000 requests        |

To upgrade to extended limits, contact [support](https://signatureapi.com/support).

## Rate limit responses

When you exceed the rate limit, the API returns a `429 Too Many Requests` response.

```json theme={null}
// HTTP Status Code 429

{
    "type": "https://signatureapi.com/docs/v1/errors/too-many-requests",
    "title": "Too many requests",
    "status": 429,
    "detail": "The client is sending too many requests per second."
}
```

## Handling rate limits

When you receive a `429` response, wait briefly before retrying. A simple approach:

1. Wait 1 second after receiving a `429` response.
2. Retry the request.
3. If you receive another `429`, double the wait time (2 seconds, then 4 seconds, and so on).
4. After 5 retries, stop and log the failure for investigation.