Allocating more RAM to Minecraft can smooth out stutters, reduce crashes with big modpacks, and make large worlds feel more responsive. After following this guide, you can expect faster load times, fewer crashes, and a much smoother experience with even the most demanding modpacks on a 4 GB or better system. This guide on how to allocate more RAM to Minecraft shows you how to do it in the official Minecraft Launcher and several popular modded launchers. It also explains what is and isn’t possible in Minecraft Bedrock.
What “Allocating More RAM” Really Means
Minecraft Java runs on the Java Virtual Machine (JVM), which enables Java applications like Minecraft to run on your computer. The JVM uses a dedicated memory pool called the heap. The size of that heap is controlled by startup options, most importantly:
- -Xms – the minimum heap size (starting RAM).
- -Xmx – the maximum heap size (the upper RAM limit).
When you “give Minecraft more RAM,” you are increasing the -Xmx value so the game can use more memory when needed. Launchers usually expose this as:
- A slider measured in MB (megabytes), or
- A text field that includes something like -Xmx4G (4 GB), -Xmx6G (6 GB), and so on.
More RAM helps most when:
- You play heavy modpacks with lots of blocks, dimensions, and entities.
- You use high render distances or big bases with many farms.
- You often crash with “out of memory” or Java heap space errors.
However, allocating a large amount of RAM to Minecraft does not guarantee improved performance. When the heap size becomes excessively large, the Java Virtual Machine (JVM) must scan and manage a larger memory area during garbage collection, which frees up memory no longer in use by the game. As a result, garbage collection events can take longer to complete, leading to noticeable pauses or temporary lag during gameplay as the JVM halts regular operations to reclaim memory.
For example, setting the memory allocation to 12 GB on a system with 16 GB of RAM can cause the game to freeze periodically during garbage collection. Therefore, it is important to select a reasonable allocation that balances performance needs without introducing these drawbacks. Quick tip: For most players, 4–6 GB is enough; avoid going above half your total RAM.
How Much RAM Should You Give Minecraft?
Before making any changes, first verify your computer’s total installed RAM. If you’re not sure how much you have, press Ctrl+Shift+Esc to open Task Manager, then check the Performance tab for your total memory (RAM). Attempting to allocate more memory than is physically available can cause system instability or crashes. Once you have determined your hardware specifications, use these rough guidelines:
Good starting points
- Vanilla or lightly modded:
2–4 GB is usually plenty on a modern system. - Medium modpacks (dozens of mods):
4–6 GB is a common sweet spot. - Very large or expert modpacks:
6–8 GB can help if you have enough memory.
Safety rules
- Avoid allocating more than about half your total RAM to Minecraft.
Your operating system and background apps also need memory. - If you have 8 GB total RAM, try 3–4 GB for Minecraft.
- If you have 16 GB or more, 4–6 GB is typically safe for heavy packs.
If you go too high, you may see problems such as the game not starting, the system slowing down, or long pauses while Java cleans up memory. If that happens, lower the allocation.
Allocating More RAM in the Official Minecraft Launcher (Java)
These steps are the same on Windows, macOS, and Linux, because they rely on the launcher’s Java arguments field.
- Open the launcher and select Java Edition
Start the Minecraft Launcher and make sure you are on the Java Edition screen, not the Bedrock Edition. - Go to the “Installations” tab
At the top, click Installations. - Choose the profile you want to change
Find the installation you use (for example, “Latest release” or a specific Fabric/Forge profile).
Hover over it, click the three dots (…), and select Edit. - Expand “More Options”
In the Edit Installation window, click More Options to show the advanced Java settings. - Locate the JVM arguments
There is a text box labeled JVM Arguments. Near the start, you will see something like:
-Xmx2G -Xms1G …
The -Xmx part is your current maximum RAM. - Change the -Xmx value
- For 4 GB, use: -Xmx4G
- For 6 GB, use: -Xmx6G
- For 8 GB, use: -Xmx8G
- Save and launch
Click Save, return to the main screen, and start the game with that installation. If the game fails to launch or crashes, revert to the previous GB value you used and try a lower number instead. - Optional: confirm the new limit in-game
Once the world is loaded, press F3 to open the debug screen.
In the top right, you’ll see a memory line (for example, Mem: 1500/6144MB).
The second number is the maximum memory the game can use; it should match what you set.
Allocating More RAM in the CurseForge (Overwolf) Launcher
CurseForge is one of the most popular ways to play modpacks. It provides RAM controls at both the global and per-profile levels.
Option 1: Set a global default for all packs
- Open CurseForge settings
Launch CurseForge and click the gear icon in the bottom-left to open settings. - Select Minecraft from game-specific settings
In the left sidebar, choose Minecraft. - Find the “Allocated Memory” section
Scroll until you see Java Settings or Allocated Memory. There will be a slider or numerical box. - Adjust the slider
RAM is shown in MB:- 2048 MB > 2GB
- 4096 MB > 4GB
- 6144 MB > 6GB
- 8192 MB > 8GB
- Close settings
The app usually saves automatically. All modpacks that rely on the global setting will now use this amount.
Option 2: Custom RAM for a single modpack
- Open “My Modpacks”
In CurseForge, go to the My Modpacks tab. - Open the pack’s options
Click the modpack tile (not the Play button), then look for a three-dot menu or Profile Options. - Enable custom memory
Turn off any “Use system memory settings” option and enable a local or custom RAM setting for that pack. - Set the RAM for that pack
Use the slider or box to assign a specific amount just for this modpack, often 6–8 GB for large packs if your PC can handle it. - Save and play
Save changes and launch the pack. It will use the value you configured instead of the global one.
Allocating More RAM in Other Popular Java Launchers
Nearly every Minecraft launcher follows a similar pattern for RAM allocation: open the Settings menu, select the Java configuration section, then adjust the Memory or RAM setting. While layouts may vary, you will almost always find the memory limit under a path such as “Settings > Java > Memory,” although launchers may use slightly different terms. For example, MultiMC refers to this option as “Maximum Memory Allocation,” Technic Launcher lists it under “Java Settings” as a “Memory” dropdown, and ATLauncher labels it as “Maximum Memory/Ram.” Recognizing these variations in terminology helps users transfer their knowledge between launchers, even when menu structures or labels differ.
ATLauncher
- Open ATLauncher and click Settings in the left sidebar.
- Go to the Java/Minecraft tab.
- Change Maximum Memory/Ram to your desired value in MB (4096 for 4 GB, 8192 for 8 GB).
- For example, open Instances, edit that instance’s settings, and set the memory there.
Technic Launcher
- Start the Technic Launcher.
- Click Launcher Options (usually in the top-right).
- Open the Java Settings tab.
- Use the Memory dropdown to allocate RAM value (2 GB, 4 GB, etc.).
MultiMC
- In MultiMC, right-click the instance you want to change and select Edit Instance.
- Click Settings in the instance window.
- Tick Memory if it is not already enabled.
- Set Maximum Memory Allocation to the desired amount in MB.
FTB App (Feed The Beast)
- Open the FTB App and go to your library.
- Select the modpack you want to configure.
- Open the pack’s settings or options.
- Adjust the RAM slider to the memory value you want.
Void Launcher
- Launch Void Launcher.
- Click the options button (usually in the top-right).
- Use the “Memory Size to Allocate to Minecraft” dropdown to choose a memory size.
The exact labels may differ slightly between versions, but the pattern is always: settings, Java or Minecraft, then memory (RAM).
Can You Allocate More RAM to Minecraft Bedrock?
This is where things are very different.
In Minecraft Bedrock, the version on Windows 10/11 (from the Microsoft Store), consoles, and mobile, you cannot manually set RAM the way you can in Java Edition. There is:
- No JVM arguments field, because Bedrock does not run on the standard Java VM.
- No built-in RAM slider or -Xmx flag.
Unlike the Java Edition, Minecraft Bedrock does not rely on the Java Virtual Machine; instead, it is built as a native application tailored for each platform. As a result, Bedrock manages memory allocation internally by requesting and using RAM based on the system’s capacity and needs, rather than exposing user-configurable options. Because the memory allocation is managed automatically by the application and constrained by the operating system and device hardware, performance tuning for Bedrock is primarily achieved by adjusting in-game graphical settings and reducing system resource usage, rather than by directly modifying RAM settings:
- Lowering render distance and simulation distance.
- Turning down graphics options such as fancy leaves, beautiful skies, or high-end shaders.
- Closing background apps so more system resources are free.
On consoles and mobile, you are at the mercy of the system, and there is no supported way to change RAM allocation. On Windows, advanced users may see third-party tools discussed online, but they are generally unsupported and can cause instability or bans, so they are not recommended.
Picking the Right RAM Amount: Practical Tips
If you are unsure where to start, these simple rules help avoid common problems:
- Start low and increase gradually.
For a heavy modpack on a 16 GB system, start with 4GB, then move up to 5–6 GB if you hit memory limits. - Listen to what the pack maintainer recommends.
Many modpack pages on CurseForge and similar sites list a recommended RAM range. - Watch the F3 screen (Java) or a system monitor.
If Minecraft is using much less memory than you allocated and still stuttering, your bottleneck may be CPU, GPU, or disk, not RAM. - Avoid maxing out your system RAM.
If you give Minecraft so much memory that your OS starts swapping and using the disk as fake RAM, everything will feel slower.
Troubleshooting RAM Problems: Quick FAQ
Game won’t launch after increasing RAM?
– Try lowering your -Xmx value or slider by a few gigabytes and restart the game. Make sure you are not allocating more RAM than your PC has available. If you are on an older or 32-bit system, the maximum usable memory is much lower, so using a modern 64-bit setup is best.
Still getting low FPS or stutters even with lots of RAM?
– Extra RAM alone can’t fix all performance issues. Reduce your render distance and other graphics options, close heavy background programs such as web browsers, and update your graphics drivers and Java. For modded Minecraft, try installing performance mods or lighter modpacks.
F3 memory numbers don’t match what you set?
– Double-check that you edited the correct profile in your launcher and are launching through it. If you’re using launchers like CurseForge, make sure your modpack is actually using the custom memory settings (not still pointing to the default). Also, verify you’re starting Minecraft from the right shortcut and not another launcher.
Quick Launcher Reference
This table serves as an efficient visual resource for locating RAM allocation options in the most commonly used Java and modded Minecraft launchers.
| Use case | Edition / Tool | Where to change RAM |
|---|---|---|
| Vanilla or simple modded via official app | Java, official launcher | Installations > Edit > More Options > JVM Arguments (-Xmx…) |
| Modpacks via CurseForge (Overwolf) | Java, CurseForge | Global: Settings > Minecraft > Allocated Memory; Per pack: My Modpacks > Profile Options |
| Instances via ATLauncher | Java, ATLauncher | Settings > Java/Minecraft > Maximum Memory (plus per>instance settings) |
| Packs via Technic Launcher | Java, Technic | Launcher Options > Java Settings > Memory dropdown |
| Instances in MultiMC | Java, MultiMC | Right-click instance > Edit > Settings > Memory |
| Packs via FTB App | Java, FTB App | Library > Pack Settings > RAM slider |
| Void Launcher packs | Java, Void Launcher | Options > Memory Size to Allocate |
| Windows/Mobile/Console Bedrock | Bedrock | No supported manual RAM control; adjust in-game settings |
To allocate more RAM in Minecraft for performance and system stability, follow these best practices: (1) configure memory allocation within your Minecraft launcher’s settings, (2) select an appropriate amount of RAM based on your hardware and gameplay needs, and (3) avoid allocating excessive memory that could strain your system. Adhering to these guidelines will promote smoother, more consistent gameplay. Enjoy longer play sessions with fewer crashes and get the most out of your Minecraft worlds.
