diff --git a/.github/workflows/gradle-test.yml b/.github/workflows/gradle-test.yml
index 932347e..45fdb4d 100644
--- a/.github/workflows/gradle-test.yml
+++ b/.github/workflows/gradle-test.yml
@@ -8,10 +8,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 17
+    - name: Set up JDK 21
       uses: actions/setup-java@v1
       with:
-        java-version: 17
+        java-version: 21
 
     - name: Build with Gradle
       run: ./gradlew build
diff --git a/README.adoc b/README.adoc
index 285c42e..951c873 100644
--- a/README.adoc
+++ b/README.adoc
@@ -27,7 +27,7 @@ This is an experimentel feature.
 * Current build state : image:https://github.com/ehmkah/imgdiff/actions/workflows/gradle-test.yml/badge.svg[link="https://github.com/ehmkah/imgdiff/actions/workflows/gradle-test.yml/badge.svg"]
 
 === Requirements
-* Java 17 or higher (project is configured to use Java 17)
+* Java 21 or higher (project is configured to use Java 21)
 
 === Setup
 * Import to intellij with gradle
diff --git a/build.gradle b/build.gradle
index 544fc31..e2dbed7 100644
--- a/build.gradle
+++ b/build.gradle
@@ -11,7 +11,7 @@ version = '1.12.0-SNAPSHOT'
 
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(17)
+        languageVersion = JavaLanguageVersion.of(21)
     }
 }
 
diff --git a/gradle.properties b/gradle.properties
index 78302cf..1f2048c 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,3 +1,3 @@
 # Java version configuration
 # Explicitly set Java version requirement
-java.version=17
\ No newline at end of file
+java.version=21
\ No newline at end of file