diff --git a/apps/manacore/apps/web/src/lib/config/storage-keys.ts b/apps/manacore/apps/web/src/lib/config/storage-keys.ts
new file mode 100644
index 000000000..496bd5f8d
--- /dev/null
+++ b/apps/manacore/apps/web/src/lib/config/storage-keys.ts
@@ -0,0 +1,16 @@
+/**
+ * Centralized localStorage keys for the ManaCore web app.
+ * All keys should be prefixed with 'manacore-' to avoid collisions.
+ */
+export const STORAGE_KEYS = {
+	/** User's preferred locale (e.g., 'de', 'en') */
+	LOCALE: 'locale',
+	/** Whether the sidebar navigation is collapsed */
+	NAV_COLLAPSED: 'manacore-nav-collapsed',
+	/** Whether the welcome page has been seen */
+	HAS_SEEN_WELCOME: 'hasSeenWelcome',
+	/** Onboarding wizard state (JSON) */
+	ONBOARDING: 'manacore-onboarding',
+	/** Dashboard widget layout (JSON) — defined in default-dashboard.ts */
+	// DASHBOARD: 'manacore-dashboard-config',
+} as const;
diff --git a/apps/manacore/apps/web/src/lib/i18n/index.ts b/apps/manacore/apps/web/src/lib/i18n/index.ts
index 69ad3c858..275efd602 100644
--- a/apps/manacore/apps/web/src/lib/i18n/index.ts
+++ b/apps/manacore/apps/web/src/lib/i18n/index.ts
@@ -1,5 +1,6 @@
 import { browser } from '$app/environment';
 import { init, register, locale, waitLocale } from 'svelte-i18n';
+import { STORAGE_KEYS } from '$lib/config/storage-keys';
 
 // Register all available locales
 register('de', () => import('./locales/de.json'));
@@ -19,7 +20,7 @@ const defaultLocale = 'de';
 function getInitialLocale(): SupportedLocale {
 	if (browser) {
 		// Check localStorage first
-		const stored = localStorage.getItem('locale');
+		const stored = localStorage.getItem(STORAGE_KEYS.LOCALE);
 		if (stored && supportedLocales.includes(stored as SupportedLocale)) {
 			return stored as SupportedLocale;
 		}
@@ -52,7 +53,7 @@ export function initI18n() {
 export function setLocale(newLocale: SupportedLocale) {
 	locale.set(newLocale);
 	if (browser) {
-		localStorage.setItem('locale', newLocale);
+		localStorage.setItem(STORAGE_KEYS.LOCALE, newLocale);
 	}
 }