What Causes the Minecraft Has Run Out of Memory Error?


The Minecraft Has Run Out of Memory error occurs when the amount of memory that your PC has available to run Minecraft  is exceeded by the game.

The amount of RAM Minecraft has to run is limited by two factors:

  • The amount of RAM your PC has installed.
  • The amount of RAM allocated to Minecraft.

First, you will want to find out how much RAM you have and compare it with our system requirements page to understand what might be causing your problem.

The amount of RAM installed on your computer is a set amount, it can’t be changed without improving your hardware.  If the amount of memory you have installed on your computer is below the system requirements then you may have to consider an upgrade or try some of our fixes to improve performance.

The amount of RAM allocated to Minecraft however can be changed. This is very useful for users who have found that they should have enough RAM to run the game, but are still coming up against this error.

The issue with running Minecraft in Java is that it is only ever allocated 1GB to run by default. This amount can be changed though, to make better use of your computer’s hardware and prevent the game from running out of memory in future. To find out how to allocate Minecraft more memory read our guide.

The amount of RAM that Minecraft needs is affected by many factors, including whether mods are installed, playing a high settings and using complex redstone machinery. The Tekkit and Technic Pack for instance include a lot of extra items that can increase the load Minecraft has upon your computer’s memory.

If you are running these mods on a computer that only meets the minimum system requirements for Minecraft then you may want to uninstall these mods and play on vanilla Minecraft instead. This should improve performance and prevent the Minecraft Has Run Out of Memory error occuring as often. This should also give you some time to try some of our fixes to make Minecraft run better first.