All free servers include 1GB RAM, and a 20GB server size limit. There is no set answer for the question of how many plugins you can run on a free server because there are too many variables.
- Server Version (Vanilla is not optimized or recommended for free servers)
- World Size
- Number of Players
- Specific requirements for individual plugins.
We recommend installing the plugins that are the most important first and seeing how the server runs. If everything runs smoothly, create a manual backup, and try adding some more. By having a backup saved it is easy to restore your settings if you add a plugin that is too much for the server.