Quick guide

How to Allocate More RAM to Minecraft

Give Minecraft more memory to reduce stutters, improve FPS, and run heavier modpacks without random crashes.

⚠️ Important: Do not use more than 50-75% of your PC's total RAM for Minecraft.
Official Minecraft Launcher CurseForge Launcher

Before you change anything

Before increasing RAM, check how much memory your PC has and decide how much you can safely dedicate to Minecraft.

  • On Windows: Open System Information and look for "Installed Physical Memory (RAM)".
  • Rule of thumb: Do not dedicate more than 50% of your total RAM to Minecraft, or your system may freeze or crash.
Quick example: If you have 8 GB of RAM, allocate 3–4 GB for Minecraft. With 16 GB you can go up to 6–8 GB comfortably.

Official Minecraft Launcher (Java Edition)

These steps apply to Minecraft Java Edition using the official Mojang/Microsoft launcher.

  1. Open the Minecraft Launcher and make sure you are on the Java Edition tab.
  2. At the top, click on "Installations".
  3. Hover your mouse over the installation you want to edit and click three dots (…) > Edit.
  4. In the window that opens, click on "More Options".
  5. Look for the field called "JVM Arguments". You will see something like: -Xmx2G -Xms2G
  6. Change the number after -Xmx to increase the maximum RAM. For example:
    • -Xmx4G → 4 GB
    • -Xmx6G → 6 GB
    • -Xmx8G → 8 GB
  7. Click "Save" to apply the changes.
  8. Start the game using that installation.
💡 Verify it worked: In-game, press F3 to open the debug screen. In the top right corner you can see your allocated memory.

CurseForge and Other Launchers

Many launchers let you adjust RAM with a simple slider, so you don't need to touch JVM arguments manually.

CurseForge Launcher

  1. Open the CurseForge app.
  2. Click the Settings (cog) icon at the bottom left.
  3. Select "Minecraft" in the left menu.
  4. In "Java Settings" section, find "Allocated Memory" slider.
  5. Move the slider to your desired amount (4096 MB = 4 GB, 8192 MB = 8 GB).
To change RAM for one specific modpack only, go to "My Modpacks" > profile options (three dots) > adjust memory there.

Other Popular Launchers

ATLauncher / FTB / Prism Launcher: Settings > Java/Minecraft > look for "Maximum Memory" or "Memory/Instance Memory" slider.

MultiMC / Prism: Right-click instance > Edit/Settings > enable "Memory" and set the maximum value.

If you can't find it, search for "Java Settings", "Memory", or "RAM" in the launcher's settings.

How much RAM should I allocate?

It depends on your total system RAM and whether you're playing vanilla or heavy modpacks.

Total System RAM Recommended for Minecraft
8 GB 3–4 GB (vanilla or light modpacks)
16 GB 6–8 GB (medium/large modpacks)
32 GB 8–12 GB (very heavy modpacks)
⚠️ Warning: Giving Minecraft too much RAM does not always improve performance and can even make it worse. Increase memory gradually until you find a stable sweet spot for your pack.

Key Takeaways

  • ✅ Allocate 3-4 GB for light gaming, 6-8 GB for heavy modpacks
  • ✅ Never allocate more than 75% of your system RAM
  • ✅ Use F3 in-game to verify your allocation worked
  • ✅ If lag persists, the issue is likely elsewhere
  • ✅ Close Chrome, Discord and other apps before playing – they eat RAM too