diff --git a/.github/workflows/.build.yaml b/.github/workflows/.build.yaml
index 8e2376f1..51d5e7b1 100644
--- a/.github/workflows/.build.yaml
+++ b/.github/workflows/.build.yaml
@@ -20,11 +20,11 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
-      - name: Setup Java v17.x
+      - name: Setup Java
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17.x
+          java-version: 21
           cache: gradle
       - name: Inject slug/short variables
         uses: rlespinasse/github-slug-action@v4
diff --git a/.github/workflows/.test.yaml b/.github/workflows/.test.yaml
index 149aa196..171b1cdd 100644
--- a/.github/workflows/.test.yaml
+++ b/.github/workflows/.test.yaml
@@ -11,11 +11,11 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
-      - name: Setup Java v17.x
+      - name: Setup Java
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17.x
+          java-version: 21
           cache: gradle
       - name: Gradle test and build
         env:
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 2334e3b8..0c420d72 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -27,11 +27,12 @@ jobs:
           languages: java
           queries: security-and-quality
 
-      - name: Set up JDK
+      - name: Setup Java
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: 21
+          cache: gradle
 
       - name: Setup Gradle
         uses: gradle/gradle-build-action@v2
diff --git a/.github/workflows/verify-branches.yaml b/.github/workflows/verify-branches.yaml
index b165ec63..9d5d9f8c 100644
--- a/.github/workflows/verify-branches.yaml
+++ b/.github/workflows/verify-branches.yaml
@@ -11,10 +11,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-java@v4
+      - name: Setup Java
+        uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17.x
+          java-version: 21
           cache: gradle
 
       # Build
diff --git a/apps/etterlatte-notifikasjoner/Dockerfile b/apps/etterlatte-notifikasjoner/Dockerfile
index 86de5667..3bd6095c 100644
--- a/apps/etterlatte-notifikasjoner/Dockerfile
+++ b/apps/etterlatte-notifikasjoner/Dockerfile
@@ -1,4 +1,4 @@
-FROM gcr.io/distroless/java17
+FROM gcr.io/distroless/java21
 ENV TZ="Europe/Oslo"
 WORKDIR /app
 COPY build/libs/*.jar ./
diff --git a/apps/etterlatte-proxy/Dockerfile b/apps/etterlatte-proxy/Dockerfile
index 9491c248..4ccf574c 100644
--- a/apps/etterlatte-proxy/Dockerfile
+++ b/apps/etterlatte-proxy/Dockerfile
@@ -1,4 +1,4 @@
-FROM ghcr.io/navikt/baseimages/temurin:17
+FROM ghcr.io/navikt/baseimages/temurin:21
 
 COPY import-vault-token.sh /init-scripts
 COPY build/libs/*.jar ./
diff --git a/buildSrc/build.gradle.kts b/buildSrc/build.gradle.kts
index 372ccfb0..a5a22c23 100644
--- a/buildSrc/build.gradle.kts
+++ b/buildSrc/build.gradle.kts
@@ -29,12 +29,12 @@ tasks {
     }
 
     withType<KotlinCompile> {
-        kotlinOptions.jvmTarget = JavaVersion.VERSION_17.toString()
+        kotlinOptions.jvmTarget = JavaVersion.VERSION_21.toString()
     }
 
     java {
-        sourceCompatibility = JavaVersion.VERSION_17
-        targetCompatibility = JavaVersion.VERSION_17
+        sourceCompatibility = JavaVersion.VERSION_21
+        targetCompatibility = JavaVersion.VERSION_21
     }
 
     withType<AnalyzeDependenciesTask> {