There can be many reasons why a Minecraft server is laggy – – Too many plugins or mods running. – The server is low on RAM and needs more memory capacity. – Too large a world for the server to manage. You may not notice any lag while playing on the world alone or with another player. But, once you expand to 4+ players, you may face sufficient lag to deteriorate gameplay experience. – Server location is a common issue and you may face client-end lag. Players closer to the server may not face any lag. – Check your Minecraft edition. – Having too many items in the world can also cause server lag.