# How to Set Up a Headless Client on Your Arma 3 Server (/docs/arma-3/headless-client)



import { Step, Steps } from 'fumadocs-ui/components/steps';

A **Headless Client (HC)** offloads AI processing from the server to a separate client instance. This improves server FPS when running missions with many AI units.

Configure the Server for Headless Client [#configure-the-server-for-headless-client]

<Steps>
  <Step>
    Stop the server and open `server.cfg` in **Files**.
  </Step>

  <Step>
    Add the headless client IP addresses:

    ```
    headlessClients[] = { "127.0.0.1" };
    localClient[] = { "127.0.0.1" };
    ```

    Use `127.0.0.1` if the HC runs on the same machine. Add additional IPs for remote HCs.
  </Step>

  <Step>
    Save and start the server.
  </Step>
</Steps>

Why Use a Headless Client? [#why-use-a-headless-client]

Arma 3's AI runs on a single thread. A headless client moves that work to a separate process, freeing the server to handle player sync and networking.

> Missions must be designed to support headless clients — not all missions offload AI automatically.

Related Guides [#related-guides]

* [Server Configuration](/docs/arma-3/configure-your-server)
* [Server Ports](/docs/arma-3/server-ports)