How much memory you need to give Minecraft depends on what version of the game you are playing, how big your world is, and how much memory your Windows computer has.

If you see Minecraft has run out of memory error, your might have to allocate more memory to Minecraft, Reduce video settings, etc.

Allocate more RAM: To do so, open Minecraft Launcher. Go to settings, and then under Java Settings, allocate more RAM. It will help, especially if you are using the mods.