How to Allocate More Memory to your Minecraft Client

When you are running a large variety of plugins or mods on your server, sometimes your client might not have enough memory to run all the tasks. Especially when you start to throw mods into the mix, the standard 2GB of allocated RAM is definitely not enough. Luckily you are able to increase and decrease the amount of memory that is allocated to your client. Which in most cases will see performance benefits, and is necessary when running a large variety of mods or plugins.

Please Note: That this will not increase the amount of RAM allocated to your server, and will only affect your client.

Step-by-Step Guide:

By increasing your launcher's memory, Minecraft will be able to handle more extensive tasks. In theory, you should be able to download mods and work with servers with a great number of plugins and custom features. Firstly, we need to check how much memory your computer actually has, this way you can determine how much memory you should allocate to Minecraft.

Increasing your memory will mean your computer is using more of its hardware just for Minecraft. You will need to ensure that you have enough memory to increase it.

How to Check How Much Memory Your Computer Has

Windows

  1. Open the start menu on your computer.
  2. Type About your PC and click the option.
  3. Under Device Specifications, you should see installed RAM. (8GB.. 16GB, etc)

Mac

  1. Click on the apple on the top left-hand side of your screen.
  2. Select About This Mac.
  3. Under memory, it should display how much RAM you have. (8GB.. 16GB, etc)

How Much Memory Should I Allocate to Minecraft?

Allocating memory is sometimes difficult when you don't know how much memory to allocate. Below is a conversion, for how much you should allocate to Minecraft. Realistically you shouldn't add the same amount of RAM your computer has, as it will have no memory to perform any other task. This is why below you can see the scale for how much to add.

PC Memory Best Amount Maximum Amount
4GB 2GB 3GB
6GB 3GB 5GB
8GB 4GB 7GB
12GB 6GB 11GB
16GB 8GB 15GB
32GB 16GB 31GB
64GB 32GB 63GB

The reason you can see the best section not increasing as much is that Minecraft does not need a large amount of memory. Unless you are running extensive plugins or mods, using shaders as well requires a lot of memory. In those cases, you should be applying more memory to your game. However using the maximum amount of RAM, will not necessarily increase your FPS, but in some cases, if you are trying to push Minecraft to its limits it can be required.

How to Allocate More Memory to Minecraft

Depending on which Launcher you are using for Minecraft, you will have to follow a step-by-step guide on each of them, for allocating more memory. Each Launcher roughly has the same method for changing the amount of memory.

Please Note: It is not recommended to use all the memory your computer has for Minecraft. As your computer still has other tasks to run, and if you try to allocate all your RAM to Minecraft and then decide to open another game, or even an internet browser your computer could experience issues. 

Vanilla / Forge

  1. Open up your Minecraft Launcher.
  2. Navigate to Installations and press New...
  3. Press More Options, scroll down and you should see JVM Arguments.
  4. Locate -Xmx2G, you might have another number in there. This number is how much RAM you have allocated to Minecraft. Change this number to how much RAM you would like in Minecraft for example -Xmx8G"
  5. Name and customize your installation how you would like, and then press save.
  6. Launch Minecraft using this installation, log into a world, and press F3. In the top right verify that the allocated memory has been changed to the number you set.

Technic 

  1. Open up your Technic Launcher.
  2. In the top right, press Launcher Options and navigate to Java Settings.
  3. Ensure your Java version has 64 bit in the title, if not refer to the bottom of this article. You should see Memory, change this to the amount of RAM you would like to allocate for example 8GB.
  4. Now launch Technic, with any modpack of your choice.
  5. Log into a world, and press F3. In the top right you should be able to verify that the allocated memory has changed to the number you set.

FTP (Feed the Beast)

  1. Firstly, open up your FTB Launcher.
  2. You will need to have installed the modpack you are wishing to use. Then press My Modpacks.
  3. Locate your modpack, and press the 3 dots in the top right of the icon.
  4. Then press the settings tab, and find Instance Memory.
  5. Change the amount of Memory using the slider, and then press Save.
  6. Launch up the modpack, login to a world, and press F3. In the top right you should be able to verify that the allocated memory has changed accordingly.

ATLauncher

  1. Open up your ATLauncher.
  2. Press Settings, in the bottom right.
  3. Click on the Java/Minecraft tab.
  4. You should see Maximum Memory/RAM, ATLauncher uses MB, so use this converter: https://www.gbmb.org/gb-to-mb
  5. On the ATLauncher, input the amount of memory that you would like to allocate, and press save.
  6. Now launch the pack that you would like.
  7. Login to a world, and press F3. In the top right you should be able to verify that the allocated memory has changed to the number you set.

CurseForge

  1. Open up your CurseForge Launcher.
  2. Navigate into Minecraft, and click on the modpack you wish to allocate more memory to.
  3. Next to the play button, you should see 3 dots, press them, and select profile options.
  4. Uncheck Use system memory settings.
  5. Use the slider to set how much memory you want to allocate. CurseForge uses MB, so use this converter: https://www.gbmb.org/gb-to-mb
  6. Press Done, and launch up the game using the edited modpack.
  7. Login to a world, and press F3. In the top right you should be able to verify that the allocated memory has changed to the number you set.

If your game is crashing often, this could mean you have not allocated enough memory to the game. You should receive a crash-report, please look for the following message to verify your client has run out of memory: java.lang.OutOfMemoryError: Java heap space

To fix the crashing issues, you need to allocate more memory to Minecraft. Please follow one of the above guides, depending on which launcher you are using.

NOTE: If you are unable to increase your memory past 2GB. This probably means the Java version you have installed is not the correct one. You need to completely close your launcher, and download the correct version of Java here: https://www.java.com/en/download/manual.jsp After installing this, you should be able to allocate more than 2GB of RAM.
If you require any further assistance, please contact our support at: https://shockbyte.com/billing/submitticket.php

Mitchell Smith

Managing Director @ Shockbyte

  • ram, memory, Minecraft client, Minecraft Java Edition, minecraft mod, minecraft no lagg, allocate more ram, Minecraft ram, allocating more ram to minecraft, more memory to minecraft
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