Java 17 (64-Bit) for Minecraft 1.18 – 1.20.4

The required LTS runtime for 1.18 through 1.20.4 Forge, Fabric, and Quilt modpacks. Applies to Minecraft 1.18, 1.19, 1.20.1 – 1.20.4.

Configuration

Java 17 (64-Bit) for Minecraft 1.18 – 1.20.4

Minecraft Range

Minecraft 1.18, 1.19, 1.20.1 – 1.20.4

Recommended Build

Eclipse Adoptium Temurin 17 LTS

JVM Flags

-XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200

Why Java 17 (64-Bit) for Minecraft 1.18 – 1.20.4 matters for Minecraft 1.18, 1.19, 1.20.1 – 1.20.4

The required LTS runtime for 1.18 through 1.20.4 Forge, Fabric, and Quilt modpacks.

Inside Prism Launcher, open **Settings** → **Java** (or override per instance under **Edit Instance** → **Settings**) and click **Auto-detect** or **Download** to select `Eclipse Adoptium Temurin 17 LTS`.

Recommended JVM flags and memory checks

• **JVM arguments:** `-XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200`. Always click **Test** in the Java settings panel to verify the runtime passes Prism's architecture check.
• **64-bit verification:** Ensure the architecture column reads `x86_64` (or `arm64`), never 32-bit `x86`, so you can allocate more than 2 GB of RAM.
• **Download launcher:** Get the latest Windows build of Prism Launcher from /download.