diff --git a/apps/compliance-portal/src/lib/i18n/resolveLanguage.ts b/apps/compliance-portal/src/lib/i18n/resolveLanguage.ts
index 78295803d..85388ba91 100644
--- a/apps/compliance-portal/src/lib/i18n/resolveLanguage.ts
+++ b/apps/compliance-portal/src/lib/i18n/resolveLanguage.ts
@@ -18,27 +18,57 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-export const SUPPORTED_LANGUAGES = ["en-US", "fr-FR"] as const;
+export const SUPPORTED_LANGUAGES = [
+  "en-US",
+  "fr-FR",
+  "de-DE",
+  "es-ES",
+  "id-ID",
+  "it-IT",
+  "ja-JP",
+  "ko-KR",
+  "pl-PL",
+  "pt-PT",
+  "tr-TR",
+  "uk-UA",
+  "zh-CN",
+] as const;
 
 export type SupportedLanguage = (typeof SUPPORTED_LANGUAGES)[number];
 
-// Collapse the browser's preferred languages to one of our supported locales:
-// any fr* tag maps to fr-FR, any en* tag maps to en-US. en-US is the ultimate
-// fallback when nothing matches. Resolving to a canonical supported tag here
-// means i18next is never asked to load an unsupported locale; fallbackLng only
-// has to cover individual missing keys.
+// Maps a two-letter language prefix (lowercased) to its canonical supported
+// tag, e.g. any "de*" browser tag resolves to "de-DE".
+const PREFIX_TO_LANGUAGE: Record<string, SupportedLanguage> = {
+  en: "en-US",
+  fr: "fr-FR",
+  de: "de-DE",
+  es: "es-ES",
+  id: "id-ID",
+  it: "it-IT",
+  ja: "ja-JP",
+  ko: "ko-KR",
+  pl: "pl-PL",
+  pt: "pt-PT",
+  tr: "tr-TR",
+  uk: "uk-UA",
+  zh: "zh-CN",
+};
+
+// Collapse the browser's preferred languages to one of our supported locales
+// by matching the two-letter language prefix (e.g. any "fr*" tag maps to
+// fr-FR). en-US is the ultimate fallback when nothing matches. Resolving to a
+// canonical supported tag here means i18next is never asked to load an
+// unsupported locale; fallbackLng only has to cover individual missing keys.
 export function resolveLanguage(): SupportedLanguage {
   const candidates = navigator.languages?.length
     ? navigator.languages
     : [navigator.language];
 
   for (const tag of candidates) {
-    const lower = tag.toLowerCase();
-    if (lower.startsWith("fr")) {
-      return "fr-FR";
-    }
-    if (lower.startsWith("en")) {
-      return "en-US";
+    const prefix = tag.toLowerCase().split("-")[0];
+    const language = PREFIX_TO_LANGUAGE[prefix];
+    if (language) {
+      return language;
     }
   }