diff --git a/frontend/src/lib/components/Footer.svelte b/frontend/src/lib/components/Footer.svelte
index 81b24e1..e20f88f 100644
--- a/frontend/src/lib/components/Footer.svelte
+++ b/frontend/src/lib/components/Footer.svelte
@@ -1,11 +1,12 @@
 <script lang="ts">
 	import { authIsTeacher } from '$stores/auth';
 	import { env } from '$env/dynamic/public';
+	import { APP_VERSION } from '$lib/version';
 </script>
 
 <footer class="footer">
 	<div class="container">
-		<p>&copy; {env.PUBLIC_COPYRIGHT_TEXT || `${new Date().getFullYear()} Elemes LMS`} <span class="version-badge">v16</span></p>
+		<p>&copy; {env.PUBLIC_COPYRIGHT_TEXT || `${new Date().getFullYear()} Elemes LMS`} <span class="version-badge">v{APP_VERSION}</span></p>
 		{#if $authIsTeacher}
 			<p><a href="/progress" class="teacher-link">Laporan Progress Siswa</a></p>
 		{/if}
diff --git a/frontend/src/lib/version.ts b/frontend/src/lib/version.ts
new file mode 100644
index 0000000..53df1da
--- /dev/null
+++ b/frontend/src/lib/version.ts
@@ -0,0 +1,6 @@
+/**
+ * Single source of truth for the app display version.
+ * Both Footer.svelte and service-worker.ts import from here.
+ * Bump this number after every feature/bugfix release.
+ */
+export const APP_VERSION = 16;