diff --git a/.github/workflows/build-master.yaml b/.github/workflows/build-master.yaml
index f49cb1bd1..3936e0069 100644
--- a/.github/workflows/build-master.yaml
+++ b/.github/workflows/build-master.yaml
@@ -27,7 +27,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: temurin
           cache: gradle
 
diff --git a/.github/workflows/build-pull-request.yaml b/.github/workflows/build-pull-request.yaml
index c07c069d0..2a8002252 100644
--- a/.github/workflows/build-pull-request.yaml
+++ b/.github/workflows/build-pull-request.yaml
@@ -22,10 +22,10 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: temurin
           cache: gradle
       - name: Kjør tester & bygg JAR
         run: ./gradlew clean test shadowjar
         env:
-          GITHUB_TOKEN: ${{ secrets.READER_TOKEN }}
\ No newline at end of file
+          GITHUB_TOKEN: ${{ secrets.READER_TOKEN }}
diff --git a/.github/workflows/deploy-preprod.yml b/.github/workflows/deploy-preprod.yml
index 750d40516..f16f6f89b 100644
--- a/.github/workflows/deploy-preprod.yml
+++ b/.github/workflows/deploy-preprod.yml
@@ -16,7 +16,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: temurin
           cache: gradle
 
diff --git a/Dockerfile b/Dockerfile
index 3d1f89c0c..af1a9eca7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ghcr.io/navikt/baseimages/temurin:17-appdynamics
+FROM ghcr.io/navikt/baseimages/temurin:21-appdynamics
 ENV APPD_ENABLED=true
 LABEL org.opencontainers.image.source=https://github.com/navikt/k9-los-api
 
diff --git a/build.gradle.kts b/build.gradle.kts
index d4bbf8721..d2581e06a 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -120,7 +120,7 @@ repositories {
 
 java {
     toolchain {
-        languageVersion.set(JavaLanguageVersion.of(17))
+        languageVersion.set(JavaLanguageVersion.of(21))
     }
 }