diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9d130f2..6594d13 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -4,7 +4,7 @@ jobs:
   build:
     strategy:
       matrix:
-        java: [17]
+        java: [21]
         os: [ubuntu-latest]
     runs-on: ${{ matrix.os }}
     env:
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 1dc95bd..6f08290 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -11,7 +11,7 @@ jobs:
     strategy:
       matrix:
         # Use these Java versions
-        java: [17]    # Current Java LTS & minimum supported by Minecraft
+        java: [21]    # Current Java LTS & minimum supported by Minecraft
         # and run on both Linux and Windows
         os: [ubuntu-latest]
     runs-on: ${{ matrix.os }}
diff --git a/build.gradle.kts b/build.gradle.kts
index 1ae92a6..30c6365 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -144,16 +144,16 @@ tasks {
 
     withType(JavaCompile::class) {
         options.encoding = "UTF-8"
-        // Minecraft 1.18 (1.18-pre2) upwards uses Java 17.
-        options.release.set(17)
+        // Minecraft 1.20.5 (24w14a) upwards uses Java 21.
+        options.release.set(21)
         options.isFork = true
         options.isIncremental = true
     }
 
     withType(KotlinCompile::class) {
         kotlinOptions {
-            // Minecraft 1.18 (1.18-pre2) upwards uses Java 17.
-            jvmTarget = "17"
+            // Minecraft 1.20.5 (24w14a) upwards uses Java 21.
+            jvmTarget = "21"
         }
     }
 
@@ -167,8 +167,8 @@ val sourcesJar: Task by tasks
 val javadocJar: Task by tasks
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_17
-    targetCompatibility = JavaVersion.VERSION_17
+    sourceCompatibility = JavaVersion.VERSION_21
+    targetCompatibility = JavaVersion.VERSION_21
 
     // Loom will automatically attach sourcesJar to a RemapSourcesJar task and to the "build" task
     // if it is present.