> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mailofly.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Usage & Rate Limits

> Rate limits and quotas applied to API requests.

To protect service availability and maintain optimal sending queues, Mailofly applies rate limits across API endpoints.

***

## Default Rate Limits

| Plan Tier      | Sending Burst     | Read / List Endpoints |
| :------------- | :---------------- | :-------------------- |
| **Free**       | 5 requests / sec  | 20 requests / sec     |
| **Basic**      | 20 requests / sec | 50 requests / sec     |
| **Pro**        | 50 requests / sec | 100 requests / sec    |
| **Enterprise** | Custom            | Custom                |

When a rate limit is exceeded, the API returns an HTTP `429 Too Many Requests` status code with a `Retry-After` header indicating seconds to wait.


## Related topics

- [Introduction](/api/index.md)
- [mailofly.dev Domain Error](/guides/domains/mailofly-dev-domain-error.md)
- [Supabase](/smtp/supabase.md)
- [Errors](/api/errors.md)
- [Custom Headers](/sending/custom-headers.md)