Minecraft Java Edition crashing, lagging or won’t launch on PC? RAM allocation (4 GB default since 26.1), drivers, mods: Mojang’s official fixes

Minecraft: Java Edition closes to the desktop, freezes, stutters or refuses to start on your PC? Since version 26.1 (March 24, 2026), the game allocates 4 GB of RAM by default instead of 2 GB, and Mojang’s own help center says PCs with less than 4 GB need to set it back by hand. Here are Mojang’s official steps, in a sensible order, as read on November 11, 2026. TricknFix did not test these steps itself: they are Mojang’s instructions, not a guarantee.

1. First: what changed in 26.1, and which version are you on?

• Minecraft Java Edition 26.1 “Tiny Takeover” (published by Mojang on March 24, 2026) changed the default JVM options: “The game now allocates 4 GB of RAM by default (up from 2 GB)”, and garbage collection moved from G1GC to ZGC on compatible devices. Mojang says the goal is a smoother game with fewer stutters, but adds that third-party launchers “may not support these changes”.

• According to Mojang’s official version list (the one the launcher uses), the latest Java Edition release on November 11, 2026 is 26.3, released September 15, 2026 (the Wilderness Bound drop). Snapshots of 26.4 are test versions: Mojang recommends playing the latest release.

• Since 26.1, the game requires Java 25; the official Minecraft Launcher installs the right Java runtime for you.

2. Low RAM (4 GB or less): set memory back to 2 GB

• Mojang’s help page on memory allocation says: if your system has 4 GB of RAM or less, decrease the allocation to 2 GB for stability. With 8 GB or more available, you can increase it.

• How: back up your worlds first. Open the Minecraft Launcher, sign in with your Microsoft account, select Minecraft: Java Edition, then the Installations tab. Pick the installation, select More Options, and copy the whole JVM arguments field into Notepad (or TextEdit on Mac) as a backup.

• Find the memory value (for example -Xmx2G or -Xmx4G) and change the number: -Xmx2G gives 2 GB, -Xmx4G gives 4 GB. Mojang’s limits: 4 GB maximum on a 32-bit system, and about half of your RAM at most on a 64-bit system. Select Save.

• If the game no longer launches, compare your edit with the backup (a typo or wrong letter case is enough to break it), paste the original back, or create a new installation.

• To check your RAM on Windows: Start, Settings, System, About.

3. Restart everything properly

• Mojang’s first step for crashes and lag: sign out of Minecraft, the Microsoft Store, the Xbox app and any Minecraft service, close them, shut down the PC, restart your router and modem (wait 20 seconds), then restart and sign in again.

4. Update Windows and your graphics drivers

• Install operating system updates and the newest graphics driver straight from AMD, NVIDIA or Intel. Mojang says stuttering or a “Pixel format not accelerated” error may come from outdated software or drivers.

• Close other programs using memory and processor, check you have enough free storage, and avoid work or school PCs, which may block Minecraft.

• Unplug controllers, headsets and other USB devices, then restart Minecraft: Mojang says they can be detected as game inputs and cause issues.

5. Mods, resource packs and video settings

• Disable mods (or add-ons) and re-add them one at a time to find the culprit. Mojang says mods can cause lag and affect gameplay in Java Edition.

• Lower advanced video settings: they need more processing power and memory.

6. Still crashing: crash report and reinstall

• Minecraft writes crash reports to the crash-reports folder of your game directory (on Windows, %appdata%\.minecraft\ by default). If there is no report, the Java virtual machine itself may have crashed: look for an hs_err_pid file in .minecraft (Minecraft Wiki, community documentation). These files help when you report a bug.

• Last resort according to Mojang: back up your worlds, then uninstall and reinstall Minecraft.

Sources (read November 11, 2026)

• Minecraft Help, Fix Minecraft: Java Edition Game Crashes by Checking Memory Allocation (undated): https://help.minecraft.net/hc/en-us/articles/39083573916941

• Minecraft Help, Fix Crashes and Lag Issues in Minecraft (undated): https://help.minecraft.net/hc/en-us/articles/27554449862285

• Minecraft Help, Troubleshoot Video and Graphics Issues in Minecraft: Java Edition (undated): https://help.minecraft.net/hc/en-us/articles/4409137348877

• Minecraft.net, Minecraft Java Edition 26.1 (March 24, 2026): https://www.minecraft.net/en-us/article/minecraft-java-edition-26-1

• Mojang version manifest (latest release 26.3, September 15, 2026): https://piston-meta.mojang.com/mc/game/version_manifest_v2.json

• Minecraft.net, Play Wilderness Bound: https://www.minecraft.net/en-us/article/play-wilderness-bound-game-drop

• Minecraft Wiki (community), Obtaining a crash report: https://minecraft.wiki/w/Tutorial:Obtaining_a_crash_report