# Does the Agora Signaling SDK limit concurrent users or channel message frequency? (/en/api-reference/faq/product/rtm_concurrency)

> For AI agents: see the complete documentation index at [llms.txt](/llms.txt).

The Agora Signaling SDK does not impose a hard limit on the number of concurrent online users. However, your pricing plan may impose a Peak Concurrent User (PCU) limit. Exceeding this limit could result in additional charges or service restrictions.

Agora recommends the following maximum number of channel messages per second for a single channel:

| Concurrent online users in a single channel | Number of channel messages per second |
| ------------------------------------------- | ------------------------------------- |
| \< 1,000                                    | \< 200                                |
| >= 1,000 and \< 10,000                      | \< 100                                |
| >= 10,000                                   | \< 30                                 |

<CalloutContainer type="info">
  <CalloutDescription>
    * If the number of messages per second exceeds the recommended values, latency can increase significantly and may also cause the following issues:
      * The user cannot send or receive messages.
      * The user always stays in the RECONNECTING state or keeps switching between the CONNECTED state and the RECONNECTING state. For other users, the current user may appear offline.
    * Agora provides a customized service to increase the number of messages per second without affecting latency or stability. Contact [support@agora.io](mailto\:support@agora.io) for more information.
  </CalloutDescription>
</CalloutContainer>