diff --git a/src/i18n/locales/de.ts b/src/i18n/locales/de.ts
new file mode 100644
index 0000000..011c359
--- /dev/null
+++ b/src/i18n/locales/de.ts
@@ -0,0 +1,113 @@
+const de = {
+  lang: 'Deutsch',
+
+  home_tagline: 'Wo Gespräche sich treffen – serverlos.',
+  home_description:
+    'Erstelle in Sekunden einen privaten Videoraum. Reines Peer-to-Peer-WebRTC – keine Konten, keine Server, keine Vermittler. Nur du, deine Leute und ein Code aus sechs Buchstaben.',
+  home_your_name: 'Dein Name',
+  home_host: 'Neues Meeting starten',
+  home_or_join: 'oder beitreten',
+  home_meeting_code: 'Meeting-Code',
+  home_meeting_code_placeholder: 'ABCXYZ',
+  home_join: 'Beitreten',
+  home_name_required_hint: 'Gib deinen Namen ein, um zu hosten oder beizutreten.',
+  home_error_name: 'Bitte gib deinen Namen ein.',
+  home_error_code: 'Der Meeting-Code muss aus 6 Buchstaben bestehen.',
+  home_footnote: 'Peer-to-Peer über WebRTC. Keine Konten, keine Server.',
+
+  footer_author: 'Autor',
+  footer_github: 'GitHub',
+  footer_feedback: 'Feedback',
+
+  meeting_invalid_code: 'Ungültiger Meeting-Code',
+  meeting_back_home: 'Zurück zur Startseite',
+  meeting_join_title: 'Meeting beitreten',
+  meeting_enter_name: 'Bitte gib deinen Namen ein, um fortzufahren.',
+  meeting_your_name: 'Dein Name',
+  meeting_join: 'Beitreten',
+
+  meeting_preparing: 'Kamera und Mikrofon werden vorbereitet…',
+  meeting_starting: 'Meeting wird gestartet…',
+  meeting_joining: 'Meeting wird beigetreten…',
+
+  meeting_error_title: 'Beitritt zum Meeting fehlgeschlagen',
+  meeting_error_default: 'Ein Fehler ist aufgetreten.',
+  meeting_error_unavailable_id:
+    'Dieser Meeting-Code wird bereits verwendet. Versuche einen anderen.',
+  meeting_error_peer_unavailable: 'Meeting nicht gefunden.',
+  meeting_error_start: 'Meeting konnte nicht gestartet werden.',
+
+  meeting_ended_host: 'Der Host hat das Meeting beendet',
+  meeting_ended_self: 'Du hast das Meeting verlassen',
+  meeting_ended_kicked: 'Du wurdest vom Host aus dem Meeting entfernt',
+
+  meeting_share_invite_aria: 'Einladung teilen',
+  meeting_person: 'Person',
+  meeting_people: 'Personen',
+
+  meeting_end_for_everyone: 'Meeting für alle beenden?',
+  meeting_leave_title: 'Meeting verlassen?',
+  meeting_end_for_everyone_body:
+    'Du bist der Host. Wenn du das Meeting beendest, werden alle getrennt.',
+  meeting_leave_body: 'Du wirst von diesem Meeting getrennt.',
+  meeting_cancel: 'Abbrechen',
+  meeting_end: 'Meeting beenden',
+  meeting_leave: 'Verlassen',
+
+  chat_title: 'Chat',
+  chat_close: 'Chat schließen',
+  chat_send: 'Nachricht senden',
+  chat_emoji: 'Emoji einfügen',
+  chat_placeholder: 'Nachricht…',
+  chat_empty: 'Noch keine Nachrichten.',
+  chat_you: 'Du',
+  chat_system_joined: (name: string) => `${name} ist beigetreten`,
+  chat_system_left: (name: string) => `${name} hat das Meeting verlassen`,
+
+  controls_mute: 'Stummschalten',
+  controls_unmute: 'Stummschaltung aufheben',
+  controls_stop_video: 'Video stoppen',
+  controls_start_video: 'Video starten',
+  controls_chat: 'Chat',
+  controls_share: 'Einladung teilen',
+  controls_participants: 'Teilnehmer',
+  controls_leave: 'Verlassen',
+
+  participants_title: 'Teilnehmer',
+  participants_close: 'Teilnehmer schließen',
+  participants_host: 'Host',
+  participants_you: 'Du',
+  participants_kick: 'Aus Meeting entfernen',
+  participants_kick_confirm_title: 'Teilnehmer entfernen?',
+  participants_kick_confirm_body: (name: string) =>
+    `${name} wird aus diesem Meeting entfernt.`,
+  participants_kick_confirm: 'Entfernen',
+  participants_system_kicked: (name: string) => `${name} wurde entfernt`,
+
+  rail_resize: 'Panels anpassen',
+
+  share_title: 'Andere einladen',
+  share_meeting_code: 'Meeting-Code',
+  share_copy_code: 'Code kopieren',
+  share_copy_link: 'Link kopieren',
+  share_copied: 'Kopiert',
+  share_invite_link: 'Einladungslink',
+  share_via: 'Teilen über',
+  share_more: 'Mehr…',
+  share_more_aria: 'Weitere Freigabeoptionen',
+  share_done: 'Fertig',
+  share_on: (network: string) => `Auf ${network} teilen`,
+  share_subject: 'Tritt meinem Meeting bei',
+  share_text: (code: string) => `Tritt meinem Meeting bei (Code: ${code})`,
+
+  tile_you: '(du)',
+  tile_host: 'Host',
+
+  theme_switch_to: (mode: string) => `In den ${mode} wechseln`,
+  theme_dark: 'Dunkelmodus',
+  theme_light: 'Hellmodus',
+
+  language_change: 'Sprache ändern',
+} as const;
+
+export default de;
diff --git a/src/i18n/locales/ko.ts b/src/i18n/locales/ko.ts
new file mode 100644
index 0000000..82b5ead
--- /dev/null
+++ b/src/i18n/locales/ko.ts
@@ -0,0 +1,113 @@
+const ko = {
+  lang: '한국어',
+
+  home_tagline: '대화가 만나는 곳, 서버 없이.',
+  home_description:
+    '몇 초 만에 비공개 화상 회의실을 만드세요. 순수 P2P WebRTC — 계정도, 서버도, 중개자도 없습니다. 당신과 사람들, 그리고 여섯 글자 코드만 있으면 됩니다.',
+  home_your_name: '이름',
+  home_host: '새 회의 시작',
+  home_or_join: '또는 참여',
+  home_meeting_code: '회의 코드',
+  home_meeting_code_placeholder: 'ABCXYZ',
+  home_join: '참여',
+  home_name_required_hint: '주최하거나 참여하려면 이름을 입력하세요.',
+  home_error_name: '이름을 입력해 주세요.',
+  home_error_code: '회의 코드는 6글자여야 합니다.',
+  home_footnote: 'WebRTC를 통한 P2P. 계정도 서버도 없습니다.',
+
+  footer_author: '제작자',
+  footer_github: 'GitHub',
+  footer_feedback: '피드백',
+
+  meeting_invalid_code: '잘못된 회의 코드',
+  meeting_back_home: '홈으로 돌아가기',
+  meeting_join_title: '회의 참여',
+  meeting_enter_name: '계속하려면 이름을 입력해 주세요.',
+  meeting_your_name: '이름',
+  meeting_join: '참여',
+
+  meeting_preparing: '카메라와 마이크를 준비하는 중…',
+  meeting_starting: '회의를 시작하는 중…',
+  meeting_joining: '회의에 참여하는 중…',
+
+  meeting_error_title: '회의에 참여할 수 없습니다',
+  meeting_error_default: '오류가 발생했습니다.',
+  meeting_error_unavailable_id:
+    '이미 사용 중인 회의 코드입니다. 다른 코드를 사용해 보세요.',
+  meeting_error_peer_unavailable: '회의를 찾을 수 없습니다.',
+  meeting_error_start: '회의를 시작하지 못했습니다.',
+
+  meeting_ended_host: '호스트가 회의를 종료했습니다',
+  meeting_ended_self: '회의에서 나갔습니다',
+  meeting_ended_kicked: '호스트에 의해 회의에서 내보내졌습니다',
+
+  meeting_share_invite_aria: '초대 공유',
+  meeting_person: '명',
+  meeting_people: '명',
+
+  meeting_end_for_everyone: '모두에 대해 회의를 종료할까요?',
+  meeting_leave_title: '회의에서 나갈까요?',
+  meeting_end_for_everyone_body:
+    '당신은 호스트입니다. 회의를 종료하면 모두 연결이 끊깁니다.',
+  meeting_leave_body: '이 회의에서 연결이 끊깁니다.',
+  meeting_cancel: '취소',
+  meeting_end: '회의 종료',
+  meeting_leave: '나가기',
+
+  chat_title: '채팅',
+  chat_close: '채팅 닫기',
+  chat_send: '메시지 보내기',
+  chat_emoji: '이모지 삽입',
+  chat_placeholder: '메시지…',
+  chat_empty: '아직 메시지가 없습니다.',
+  chat_you: '나',
+  chat_system_joined: (name: string) => `${name}님이 참여했습니다`,
+  chat_system_left: (name: string) => `${name}님이 나갔습니다`,
+
+  controls_mute: '음소거',
+  controls_unmute: '음소거 해제',
+  controls_stop_video: '비디오 중지',
+  controls_start_video: '비디오 시작',
+  controls_chat: '채팅',
+  controls_share: '초대 공유',
+  controls_participants: '참가자',
+  controls_leave: '나가기',
+
+  participants_title: '참가자',
+  participants_close: '참가자 닫기',
+  participants_host: '호스트',
+  participants_you: '나',
+  participants_kick: '회의에서 내보내기',
+  participants_kick_confirm_title: '참가자를 내보낼까요?',
+  participants_kick_confirm_body: (name: string) =>
+    `${name}님이 이 회의에서 내보내집니다.`,
+  participants_kick_confirm: '내보내기',
+  participants_system_kicked: (name: string) => `${name}님이 내보내졌습니다`,
+
+  rail_resize: '패널 크기 조정',
+
+  share_title: '다른 사람 초대',
+  share_meeting_code: '회의 코드',
+  share_copy_code: '코드 복사',
+  share_copy_link: '링크 복사',
+  share_copied: '복사됨',
+  share_invite_link: '초대 링크',
+  share_via: '공유 방법',
+  share_more: '더 보기…',
+  share_more_aria: '추가 공유 옵션',
+  share_done: '완료',
+  share_on: (network: string) => `${network}에 공유`,
+  share_subject: '내 회의에 참여하세요',
+  share_text: (code: string) => `내 회의에 참여하세요 (코드: ${code})`,
+
+  tile_you: '(나)',
+  tile_host: '호스트',
+
+  theme_switch_to: (mode: string) => `${mode} 모드로 전환`,
+  theme_dark: '다크',
+  theme_light: '라이트',
+
+  language_change: '언어 변경',
+} as const;
+
+export default ko;
diff --git a/src/i18n/locales/pt.ts b/src/i18n/locales/pt.ts
new file mode 100644
index 0000000..cbe03f3
--- /dev/null
+++ b/src/i18n/locales/pt.ts
@@ -0,0 +1,113 @@
+const pt = {
+  lang: 'Português',
+
+  home_tagline: 'Onde as conversas se encontram, sem servidores.',
+  home_description:
+    'Crie uma sala de vídeo privada em segundos. WebRTC puro ponto a ponto — sem contas, sem servidores, sem intermediários. Só você, as suas pessoas e um código de seis letras.',
+  home_your_name: 'Seu nome',
+  home_host: 'Iniciar nova reunião',
+  home_or_join: 'ou entrar',
+  home_meeting_code: 'Código da reunião',
+  home_meeting_code_placeholder: 'ABCXYZ',
+  home_join: 'Entrar',
+  home_name_required_hint: 'Digite seu nome para hospedar ou entrar.',
+  home_error_name: 'Por favor, digite seu nome.',
+  home_error_code: 'O código da reunião deve ter 6 letras.',
+  home_footnote: 'Ponto a ponto via WebRTC. Sem contas, sem servidores.',
+
+  footer_author: 'Autor',
+  footer_github: 'GitHub',
+  footer_feedback: 'Feedback',
+
+  meeting_invalid_code: 'Código de reunião inválido',
+  meeting_back_home: 'Voltar ao início',
+  meeting_join_title: 'Entrar na reunião',
+  meeting_enter_name: 'Por favor, digite seu nome para continuar.',
+  meeting_your_name: 'Seu nome',
+  meeting_join: 'Entrar',
+
+  meeting_preparing: 'Preparando sua câmera e microfone…',
+  meeting_starting: 'Iniciando a reunião…',
+  meeting_joining: 'Entrando na reunião…',
+
+  meeting_error_title: 'Não foi possível entrar na reunião',
+  meeting_error_default: 'Ocorreu um erro.',
+  meeting_error_unavailable_id:
+    'Este código de reunião já está em uso. Tente outro.',
+  meeting_error_peer_unavailable: 'Reunião não encontrada.',
+  meeting_error_start: 'Falha ao iniciar a reunião.',
+
+  meeting_ended_host: 'O anfitrião encerrou a reunião',
+  meeting_ended_self: 'Você saiu da reunião',
+  meeting_ended_kicked: 'Você foi removido da reunião pelo anfitrião',
+
+  meeting_share_invite_aria: 'Compartilhar convite',
+  meeting_person: 'pessoa',
+  meeting_people: 'pessoas',
+
+  meeting_end_for_everyone: 'Encerrar a reunião para todos?',
+  meeting_leave_title: 'Sair da reunião?',
+  meeting_end_for_everyone_body:
+    'Você é o anfitrião. Encerrar a reunião desconectará todos.',
+  meeting_leave_body: 'Você será desconectado desta reunião.',
+  meeting_cancel: 'Cancelar',
+  meeting_end: 'Encerrar reunião',
+  meeting_leave: 'Sair',
+
+  chat_title: 'Bate-papo',
+  chat_close: 'Fechar bate-papo',
+  chat_send: 'Enviar mensagem',
+  chat_emoji: 'Inserir emoji',
+  chat_placeholder: 'Mensagem…',
+  chat_empty: 'Ainda não há mensagens.',
+  chat_you: 'Você',
+  chat_system_joined: (name: string) => `${name} entrou`,
+  chat_system_left: (name: string) => `${name} saiu`,
+
+  controls_mute: 'Silenciar',
+  controls_unmute: 'Ativar som',
+  controls_stop_video: 'Parar vídeo',
+  controls_start_video: 'Iniciar vídeo',
+  controls_chat: 'Bate-papo',
+  controls_share: 'Compartilhar convite',
+  controls_participants: 'Participantes',
+  controls_leave: 'Sair',
+
+  participants_title: 'Participantes',
+  participants_close: 'Fechar participantes',
+  participants_host: 'Anfitrião',
+  participants_you: 'Você',
+  participants_kick: 'Remover da reunião',
+  participants_kick_confirm_title: 'Remover participante?',
+  participants_kick_confirm_body: (name: string) =>
+    `${name} será removido desta reunião.`,
+  participants_kick_confirm: 'Remover',
+  participants_system_kicked: (name: string) => `${name} foi removido`,
+
+  rail_resize: 'Redimensionar painéis',
+
+  share_title: 'Convidar outras pessoas',
+  share_meeting_code: 'Código da reunião',
+  share_copy_code: 'Copiar código',
+  share_copy_link: 'Copiar link',
+  share_copied: 'Copiado',
+  share_invite_link: 'Link de convite',
+  share_via: 'Compartilhar via',
+  share_more: 'Mais…',
+  share_more_aria: 'Mais opções de compartilhamento',
+  share_done: 'Concluído',
+  share_on: (network: string) => `Compartilhar no ${network}`,
+  share_subject: 'Entre na minha reunião',
+  share_text: (code: string) => `Entre na minha reunião (código: ${code})`,
+
+  tile_you: '(você)',
+  tile_host: 'Anfitrião',
+
+  theme_switch_to: (mode: string) => `Mudar para o modo ${mode}`,
+  theme_dark: 'escuro',
+  theme_light: 'claro',
+
+  language_change: 'Alterar idioma',
+} as const;
+
+export default pt;
diff --git a/src/i18n/locales/ru.ts b/src/i18n/locales/ru.ts
new file mode 100644
index 0000000..63ccfa5
--- /dev/null
+++ b/src/i18n/locales/ru.ts
@@ -0,0 +1,115 @@
+const ru = {
+  lang: 'Русский',
+
+  home_tagline: 'Место встречи разговоров — без серверов.',
+  home_description:
+    'Создайте приватную видеокомнату за секунды. Чистый P2P WebRTC — без аккаунтов, серверов и посредников. Только вы, ваши люди и код из шести букв.',
+  home_your_name: 'Ваше имя',
+  home_host: 'Создать встречу',
+  home_or_join: 'или присоединиться',
+  home_meeting_code: 'Код встречи',
+  home_meeting_code_placeholder: 'ABCXYZ',
+  home_join: 'Войти',
+  home_name_required_hint:
+    'Введите имя, чтобы создать встречу или присоединиться.',
+  home_error_name: 'Пожалуйста, введите ваше имя.',
+  home_error_code: 'Код встречи должен состоять из 6 букв.',
+  home_footnote: 'P2P через WebRTC. Без аккаунтов и серверов.',
+
+  footer_author: 'Автор',
+  footer_github: 'GitHub',
+  footer_feedback: 'Обратная связь',
+
+  meeting_invalid_code: 'Неверный код встречи',
+  meeting_back_home: 'На главную',
+  meeting_join_title: 'Присоединиться к встрече',
+  meeting_enter_name: 'Пожалуйста, введите имя, чтобы продолжить.',
+  meeting_your_name: 'Ваше имя',
+  meeting_join: 'Войти',
+
+  meeting_preparing: 'Подготовка камеры и микрофона…',
+  meeting_starting: 'Запуск встречи…',
+  meeting_joining: 'Подключение к встрече…',
+
+  meeting_error_title: 'Не удалось присоединиться к встрече',
+  meeting_error_default: 'Произошла ошибка.',
+  meeting_error_unavailable_id:
+    'Этот код встречи уже используется. Попробуйте другой.',
+  meeting_error_peer_unavailable: 'Встреча не найдена.',
+  meeting_error_start: 'Не удалось запустить встречу.',
+
+  meeting_ended_host: 'Организатор завершил встречу',
+  meeting_ended_self: 'Вы покинули встречу',
+  meeting_ended_kicked: 'Организатор удалил вас из встречи',
+
+  meeting_share_invite_aria: 'Поделиться приглашением',
+  meeting_person: 'участник',
+  meeting_people: 'участников',
+
+  meeting_end_for_everyone: 'Завершить встречу для всех?',
+  meeting_leave_title: 'Покинуть встречу?',
+  meeting_end_for_everyone_body:
+    'Вы организатор. Завершение встречи отключит всех участников.',
+  meeting_leave_body: 'Вы будете отключены от этой встречи.',
+  meeting_cancel: 'Отмена',
+  meeting_end: 'Завершить встречу',
+  meeting_leave: 'Выйти',
+
+  chat_title: 'Чат',
+  chat_close: 'Закрыть чат',
+  chat_send: 'Отправить сообщение',
+  chat_emoji: 'Вставить эмодзи',
+  chat_placeholder: 'Сообщение…',
+  chat_empty: 'Сообщений пока нет.',
+  chat_you: 'Вы',
+  chat_system_joined: (name: string) => `${name} присоединился(ась)`,
+  chat_system_left: (name: string) => `${name} вышел(ла)`,
+
+  controls_mute: 'Выключить микрофон',
+  controls_unmute: 'Включить микрофон',
+  controls_stop_video: 'Выключить видео',
+  controls_start_video: 'Включить видео',
+  controls_chat: 'Чат',
+  controls_share: 'Поделиться приглашением',
+  controls_participants: 'Участники',
+  controls_leave: 'Выйти',
+
+  participants_title: 'Участники',
+  participants_close: 'Закрыть участников',
+  participants_host: 'Организатор',
+  participants_you: 'Вы',
+  participants_kick: 'Удалить из встречи',
+  participants_kick_confirm_title: 'Удалить участника?',
+  participants_kick_confirm_body: (name: string) =>
+    `${name} будет удалён из этой встречи.`,
+  participants_kick_confirm: 'Удалить',
+  participants_system_kicked: (name: string) => `${name} удалён`,
+
+  rail_resize: 'Изменить размер панелей',
+
+  share_title: 'Пригласить других',
+  share_meeting_code: 'Код встречи',
+  share_copy_code: 'Копировать код',
+  share_copy_link: 'Копировать ссылку',
+  share_copied: 'Скопировано',
+  share_invite_link: 'Ссылка-приглашение',
+  share_via: 'Поделиться через',
+  share_more: 'Ещё…',
+  share_more_aria: 'Дополнительные варианты',
+  share_done: 'Готово',
+  share_on: (network: string) => `Поделиться в ${network}`,
+  share_subject: 'Присоединяйтесь к моей встрече',
+  share_text: (code: string) =>
+    `Присоединяйтесь к моей встрече (код: ${code})`,
+
+  tile_you: '(вы)',
+  tile_host: 'Организатор',
+
+  theme_switch_to: (mode: string) => `Переключить на ${mode} тему`,
+  theme_dark: 'тёмную',
+  theme_light: 'светлую',
+
+  language_change: 'Изменить язык',
+} as const;
+
+export default ru;
diff --git a/src/i18n/translations.ts b/src/i18n/translations.ts
index b74c2d3..151c908 100644
--- a/src/i18n/translations.ts
+++ b/src/i18n/translations.ts
@@ -8,6 +8,10 @@ import zh from './locales/zh';
 import fr from './locales/fr';
 import es from './locales/es';
 import ja from './locales/ja';
+import de from './locales/de';
+import pt from './locales/pt';
+import ko from './locales/ko';
+import ru from './locales/ru';
 import { getLanguagePreference } from './LocalLanguagePreference';
 
 const TranslationsPerLang: Record<SupportedLanguages, Translations> = {
@@ -16,6 +20,10 @@ const TranslationsPerLang: Record<SupportedLanguages, Translations> = {
   fr,
   es,
   ja,
+  de,
+  pt,
+  ko,
+  ru,
 };
 
 export function detectDefaultLocale(): SupportedLanguages {
diff --git a/src/i18n/translations.type.test.ts b/src/i18n/translations.type.test.ts
index 55bf6c3..49aee28 100644
--- a/src/i18n/translations.type.test.ts
+++ b/src/i18n/translations.type.test.ts
@@ -6,7 +6,7 @@ describe('supportLanguage', () => {
   });
 
   it('returns undefined for unsupported codes', () => {
-    expect(supportLanguage('de')).toBeUndefined();
+    expect(supportLanguage('it')).toBeUndefined();
     expect(supportLanguage('')).toBeUndefined();
     expect(supportLanguage('EN')).toBeUndefined();
   });
diff --git a/src/i18n/translations.type.ts b/src/i18n/translations.type.ts
index 59c517b..58dd6c4 100644
--- a/src/i18n/translations.type.ts
+++ b/src/i18n/translations.type.ts
@@ -1,6 +1,16 @@
 import en from './locales/en';
 
-export const SUPPORTED_LANGUAGES = ['en', 'zh', 'fr', 'es', 'ja'] as const;
+export const SUPPORTED_LANGUAGES = [
+  'en',
+  'zh',
+  'fr',
+  'es',
+  'ja',
+  'de',
+  'pt',
+  'ko',
+  'ru',
+] as const;
 
 export type SupportedLanguages = typeof SUPPORTED_LANGUAGES[number];