# API Rate Limits

Our primary goal is to provide a reliable and consistent service to all our users. By implementing these rate limits, we aim to:

* **Ensure fair usage**: Prevent any single user from consuming excessive resources.
* **Improve performance**: Maintain high performance and availability for all users.
* **Enhance stability**: Reduce the likelihood of service interruptions and downtime.

**Here are some common aspects of API rate limits:**

1. **Request Limit**: The maximum number of requests allowed within a specified period (e.g., per minute, hour, or day).
2. **Burst Limit**: The maximum number of requests allowed in a short burst. This is usually higher than the sustained request limit but applies over a much shorter time frame.
3. **Quota Limit**: A cumulative limit over a longer period, such as the total number of requests allowed per month.
4. **User/IP Limits**: Limits that apply per user or per IP address to prevent a single user or IP from consuming excessive resources.
5. **Endpoint-specific Limits**: Different limits for different API endpoints based on their resource intensity or importance.
6. **Concurrent Requests Limit**: The maximum number of concurrent API calls that can be made.

When the rate limit is exceeded, the API typically responds with an `HTTP status code`such as `429 Too Many Requests.` The response may include information about when the rate limit will reset and how long to wait before making additional requests.

## Default Rate Limits

<table><thead><tr><th width="129">API</th><th>Endpoint</th><th width="243">Rate Limit</th><th>Description</th></tr></thead><tbody><tr><td>REST</td><td>/sms/send</td><td><ul><li>600 RPM or 10 RPS</li><li>Submit up to 100 Numbers Per Request</li></ul></td><td> Global Limit</td></tr><tr><td>REST</td><td>/sms/status</td><td>600 RPM or 10 RPS</td><td> Global Limit</td></tr><tr><td>REST</td><td>/account/balance</td><td>60 RPM or 1 RPS</td><td> Global Limit</td></tr><tr><td>SMPP</td><td>Send SMS</td><td>10 TPS</td><td>Adjustable Limit</td></tr></tbody></table>

## Abbrivations

<table><thead><tr><th width="208">Term</th><th>Description</th></tr></thead><tbody><tr><td>API</td><td>Application Programming Interface</td></tr><tr><td>HTTP</td><td>Hypertext Transfer Protocol</td></tr><tr><td>REST API</td><td>Representational State Transfer Application Programming Interface</td></tr><tr><td>SMPP</td><td>Short Message Peer-to-Peer Protocol</td></tr><tr><td>IP</td><td>Internet Protocol</td></tr><tr><td>X-RateLimit-Limit</td><td>Maximum no. of requests allowed in the current period</td></tr><tr><td>RPM</td><td>Requests Per Minute</td></tr><tr><td>RPS</td><td>Requests Per Second</td></tr><tr><td>TPS</td><td>Transactions Per Second</td></tr></tbody></table>


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