diff --git a/.gitea/workflows/docker.yml b/.gitea/workflows/docker.yml
index e82ab6b..d8ae0d0 100644
--- a/.gitea/workflows/docker.yml
+++ b/.gitea/workflows/docker.yml
@@ -10,8 +10,20 @@ env:
   REGISTRY: gitea.lokcal.de
 
 jobs:
+  version:
+    runs-on: ubuntu-latest
+    outputs:
+      version: ${{ steps.v.outputs.version }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - id: v
+        run: echo "version=$(./scripts/version.sh)" >> "$GITHUB_OUTPUT"
+
   backend:
     runs-on: ubuntu-latest
+    needs: version
     steps:
       - uses: actions/checkout@v4
       - name: Login to registry
@@ -25,12 +37,15 @@ jobs:
         with:
           context: ./backend
           push: true
+          build-args: |
+            VERSION=${{ needs.version.outputs.version }}
           tags: |
             ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-backend:latest
-            ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-backend:${{ gitea.sha }}
+            ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-backend:${{ needs.version.outputs.version }}
 
   frontend:
     runs-on: ubuntu-latest
+    needs: version
     steps:
       - uses: actions/checkout@v4
       - name: Login to registry
@@ -46,4 +61,4 @@ jobs:
           push: true
           tags: |
             ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-frontend:latest
-            ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-frontend:${{ gitea.sha }}
+            ${{ env.REGISTRY }}/${{ gitea.repository_owner }}/streamrip-ui-frontend:${{ needs.version.outputs.version }}
diff --git a/README.md b/README.md
index db56601..88a92db 100644
--- a/README.md
+++ b/README.md
@@ -97,6 +97,19 @@ services:
 
 CI (`.gitea/workflows/ci.yml`): Backend-Tests + Docker-Builds beider Images bei jedem Push auf `main`.
 
+## Versionierung (automatisch, CalVer)
+
+`scripts/version.sh` erzeugt `DATUM.Commitanzahl` (z. B. `2026.10.04.7`, sonst `dev`).
+Lokal vor dem Bauen exportieren, die Action macht das selbst:
+
+```bash
+export APP_VERSION=$(./scripts/version.sh)
+docker compose up --build -d
+```
+
+Die Version steckt im Backend-Image (`GET /api/version`), steht im Header der UI
+und taggt die Registry-Images (`:latest` + `:2026.10.04.7`).
+
 ## API-Überblick (Backend)
 
 - `GET /api/search?type=track|album|artist|playlist|podcast&q=..`
diff --git a/backend/Dockerfile b/backend/Dockerfile
index f95ae20..945ad06 100644
--- a/backend/Dockerfile
+++ b/backend/Dockerfile
@@ -21,6 +21,9 @@ RUN pip install --no-cache-dir -r requirements.txt && pip install --no-cache-dir
 COPY app ./app
 RUN chown -R appuser:appuser /app
 
+ARG VERSION=dev
+ENV APP_VERSION=$VERSION
+
 USER appuser
 
 EXPOSE 8000
diff --git a/backend/app/core/settings.py b/backend/app/core/settings.py
index 08fc0e5..50fd4b8 100644
--- a/backend/app/core/settings.py
+++ b/backend/app/core/settings.py
@@ -9,6 +9,7 @@ CONFIG_PATH = os.environ.get(
 DOWNLOAD_DIR = os.environ.get(
     "STREAMRIP_DOWNLOAD_DIR", str(Path.home() / "StreamripDownloads")
 )
+APP_VERSION = os.environ.get("APP_VERSION", "dev")
 DEFAULT_QUALITY = int(os.environ.get("STREAMRIP_DEFAULT_QUALITY", "2"))
 DEFAULT_CODEC = os.environ.get("STREAMRIP_DEFAULT_CODEC", "")
 SOURCES = ["deezer"]
diff --git a/backend/app/main.py b/backend/app/main.py
index 2bd0b1e..fa46218 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -19,6 +19,11 @@ def health():
     return {"status": "ok"}
 
 
+@app.get("/api/version")
+def version():
+    return {"version": settings.APP_VERSION}
+
+
 @app.get("/api/sources")
 def sources():
     return {"sources": settings.SOURCES}
diff --git a/backend/tests/test_health.py b/backend/tests/test_health.py
index 7c66d77..1233009 100644
--- a/backend/tests/test_health.py
+++ b/backend/tests/test_health.py
@@ -14,3 +14,13 @@ def test_sources_deezer_only():
     r = c.get("/api/sources")
     assert r.status_code == 200
     assert r.json()["sources"] == ["deezer"]
+
+
+def test_version_endpoint(monkeypatch):
+    from app.core import settings
+
+    monkeypatch.setattr(settings, "APP_VERSION", "2026.10.04.7")
+    c = TestClient(app)
+    r = c.get("/api/version")
+    assert r.status_code == 200
+    assert r.json() == {"version": "2026.10.04.7"}
diff --git a/docker-compose.yml b/docker-compose.yml
index 2c93626..784bcb1 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -5,6 +5,7 @@ services:
       args:
         UID: ${UID:-1000}
         GID: ${GID:-1000}
+        VERSION: ${APP_VERSION:-dev}
     ports:
       - "${BACKEND_HOST_PORT:-8000}:${BACKEND_PORT:-8000}"
     environment:
diff --git a/frontend/app/components/Header.tsx b/frontend/app/components/Header.tsx
index 9835c06..8da9000 100644
--- a/frontend/app/components/Header.tsx
+++ b/frontend/app/components/Header.tsx
@@ -18,6 +18,7 @@ const NAV = [
 export default function Header() {
   const pathname = usePathname();
   const [backendOk, setBackendOk] = useState<boolean | null>(null);
+  const [appVersion, setAppVersion] = useState("");
   const [theme, setTheme] = useState<"dark" | "light">("dark");
   const [basketCount, setBasketCount] = useState(0);
 
@@ -63,6 +64,12 @@ export default function Header() {
       .catch(() => {
         if (alive) setBackendOk(false);
       });
+    fetch("/api/version")
+      .then((r) => r.json())
+      .then((b) => {
+        if (alive && b?.version) setAppVersion(b.version);
+      })
+      .catch(() => {});
     return () => {
       alive = false;
     };
@@ -102,6 +109,11 @@ export default function Header() {
             }}
           />
           <span style={{ fontWeight: 700, fontSize: 18, letterSpacing: "-0.01em" }}>streamrip-ui</span>
+          {appVersion && (
+            <span className="muted" style={{ fontSize: 12 }} title="App-Version">
+              v{appVersion}
+            </span>
+          )}
         </Link>
         <nav style={{ display: "flex", gap: 4, flex: 1 }}>
           {NAV.map((item) => {
diff --git a/scripts/version.sh b/scripts/version.sh
new file mode 100755
index 0000000..e42167f
--- /dev/null
+++ b/scripts/version.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+# Print the app version: YYYY.MM.DD.<total-commit-count> (e.g. 2026.10.04.7).
+# Falls back to "dev" outside a git checkout.
+set -eu
+DATE=$(date +%Y.%m.%d)
+if COUNT=$(git rev-list --count HEAD 2>/dev/null); then
+    echo "${DATE}.${COUNT}"
+else
+    echo "dev"
+fi