diff --git a/lang/ar/posts.php b/lang/ar/posts.php
index bf614f06..49321ed8 100644
--- a/lang/ar/posts.php
+++ b/lang/ar/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'إضافة :count',
         ],
 
+        'alt_text' => [
+            'label' => 'نص بديل',
+            'edit' => 'تحرير النص البديل',
+            'placeholder' => 'صف هذه الصورة للأشخاص الذين يستخدمون برامج قراءة الشاشة',
+            'hint' => 'يُنشر على المنصات التي تدعم أوصاف الصور.',
+            'badge' => 'ALT',
+            'save' => 'حفظ',
+        ],
+
         'emoji_picker' => [
             'search' => 'البحث عن رمز تعبيري',
             'empty' => 'لم يتم العثور على رموز تعبيرية',
diff --git a/lang/de/posts.php b/lang/de/posts.php
index f07a1de4..6fc1d048 100644
--- a/lang/de/posts.php
+++ b/lang/de/posts.php
@@ -380,6 +380,15 @@
             'add_count' => ':count hinzufügen',
         ],
 
+        'alt_text' => [
+            'label' => 'Alternativtext',
+            'edit' => 'Alternativtext bearbeiten',
+            'placeholder' => 'Beschreibe dieses Bild für Menschen, die Screenreader verwenden',
+            'hint' => 'Wird auf Plattformen veröffentlicht, die Bildbeschreibungen unterstützen.',
+            'badge' => 'ALT',
+            'save' => 'Speichern',
+        ],
+
         'emoji_picker' => [
             'search' => 'Emoji suchen',
             'empty' => 'Keine Emojis gefunden',
diff --git a/lang/el/posts.php b/lang/el/posts.php
index b32f2dd8..0b6c8133 100644
--- a/lang/el/posts.php
+++ b/lang/el/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Προσθήκη :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Εναλλακτικό κείμενο',
+            'edit' => 'Επεξεργασία εναλλακτικού κειμένου',
+            'placeholder' => 'Περιγράψτε αυτήν την εικόνα για άτομα που χρησιμοποιούν προγράμματα ανάγνωσης οθόνης',
+            'hint' => 'Δημοσιεύεται σε πλατφόρμες που υποστηρίζουν περιγραφές εικόνων.',
+            'badge' => 'ALT',
+            'save' => 'Αποθήκευση',
+        ],
+
         'emoji_picker' => [
             'search' => 'Αναζήτηση emoji',
             'empty' => 'Δεν βρέθηκαν emoji',
diff --git a/lang/en/posts.php b/lang/en/posts.php
index e4f52fed..87a0af78 100644
--- a/lang/en/posts.php
+++ b/lang/en/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Add :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Alt text',
+            'edit' => 'Edit alt text',
+            'placeholder' => 'Describe this image for people using screen readers',
+            'hint' => 'Published to platforms that support image descriptions.',
+            'badge' => 'ALT',
+            'save' => 'Save',
+        ],
+
         'emoji_picker' => [
             'search' => 'Search emoji',
             'empty' => 'No emojis found',
diff --git a/lang/es/posts.php b/lang/es/posts.php
index 61509fd8..e73b1afe 100644
--- a/lang/es/posts.php
+++ b/lang/es/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Agregar :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Texto alternativo',
+            'edit' => 'Editar texto alternativo',
+            'placeholder' => 'Describe esta imagen para las personas que usan lectores de pantalla',
+            'hint' => 'Se publica en las plataformas que admiten descripciones de imágenes.',
+            'badge' => 'ALT',
+            'save' => 'Guardar',
+        ],
+
         'emoji_picker' => [
             'search' => 'Buscar emoji',
             'empty' => 'No se encontraron emojis',
diff --git a/lang/fr/posts.php b/lang/fr/posts.php
index e228799f..79a251d1 100644
--- a/lang/fr/posts.php
+++ b/lang/fr/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Ajouter :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Texte alternatif',
+            'edit' => 'Modifier le texte alternatif',
+            'placeholder' => 'Décrivez cette image pour les personnes utilisant un lecteur d\'écran',
+            'hint' => 'Publié sur les plateformes qui prennent en charge les descriptions d\'images.',
+            'badge' => 'ALT',
+            'save' => 'Enregistrer',
+        ],
+
         'emoji_picker' => [
             'search' => 'Rechercher un émoji',
             'empty' => 'Aucun émoji trouvé',
diff --git a/lang/it/posts.php b/lang/it/posts.php
index e98a6a98..504c60cd 100644
--- a/lang/it/posts.php
+++ b/lang/it/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Aggiungi :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Testo alternativo',
+            'edit' => 'Modifica testo alternativo',
+            'placeholder' => 'Descrivi questa immagine per le persone che usano screen reader',
+            'hint' => 'Pubblicato sulle piattaforme che supportano le descrizioni delle immagini.',
+            'badge' => 'ALT',
+            'save' => 'Salva',
+        ],
+
         'emoji_picker' => [
             'search' => 'Cerca emoji',
             'empty' => 'Nessuna emoji trovata',
diff --git a/lang/ja/posts.php b/lang/ja/posts.php
index 2bbc2efa..5b76fec0 100644
--- a/lang/ja/posts.php
+++ b/lang/ja/posts.php
@@ -378,6 +378,15 @@
             'add_count' => ':count 件を追加',
         ],
 
+        'alt_text' => [
+            'label' => '代替テキスト',
+            'edit' => '代替テキストを編集',
+            'placeholder' => 'スクリーンリーダーを使用する人のためにこの画像を説明してください',
+            'hint' => '画像の説明に対応しているプラットフォームに公開されます。',
+            'badge' => 'ALT',
+            'save' => '保存',
+        ],
+
         'emoji_picker' => [
             'search' => '絵文字を検索',
             'empty' => '絵文字が見つかりません',
diff --git a/lang/ko/posts.php b/lang/ko/posts.php
index 44fdd030..dc7932ae 100644
--- a/lang/ko/posts.php
+++ b/lang/ko/posts.php
@@ -378,6 +378,15 @@
             'add_count' => ':count개 추가',
         ],
 
+        'alt_text' => [
+            'label' => '대체 텍스트',
+            'edit' => '대체 텍스트 편집',
+            'placeholder' => '화면 낭독 프로그램을 사용하는 사람들을 위해 이 이미지를 설명하세요',
+            'hint' => '이미지 설명을 지원하는 플랫폼에 게시됩니다.',
+            'badge' => 'ALT',
+            'save' => '저장',
+        ],
+
         'emoji_picker' => [
             'search' => '이모지 검색',
             'empty' => '이모지를 찾을 수 없습니다',
diff --git a/lang/nl/posts.php b/lang/nl/posts.php
index 888d9985..d76ddba1 100644
--- a/lang/nl/posts.php
+++ b/lang/nl/posts.php
@@ -378,6 +378,15 @@
             'add_count' => ':count toevoegen',
         ],
 
+        'alt_text' => [
+            'label' => 'Alt-tekst',
+            'edit' => 'Alt-tekst bewerken',
+            'placeholder' => 'Beschrijf deze afbeelding voor mensen die schermlezers gebruiken',
+            'hint' => 'Wordt gepubliceerd op platforms die afbeeldingsbeschrijvingen ondersteunen.',
+            'badge' => 'ALT',
+            'save' => 'Opslaan',
+        ],
+
         'emoji_picker' => [
             'search' => 'Emoji zoeken',
             'empty' => 'Geen emoji\'s gevonden',
diff --git a/lang/pl/posts.php b/lang/pl/posts.php
index 5f4cf0b7..162fd3e0 100644
--- a/lang/pl/posts.php
+++ b/lang/pl/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Dodaj :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Tekst alternatywny',
+            'edit' => 'Edytuj tekst alternatywny',
+            'placeholder' => 'Opisz ten obraz dla osób korzystających z czytników ekranu',
+            'hint' => 'Publikowany na platformach obsługujących opisy obrazów.',
+            'badge' => 'ALT',
+            'save' => 'Zapisz',
+        ],
+
         'emoji_picker' => [
             'search' => 'Szukaj emoji',
             'empty' => 'Nie znaleziono emoji',
diff --git a/lang/pt-BR/posts.php b/lang/pt-BR/posts.php
index 72a8a361..b0d4adbb 100644
--- a/lang/pt-BR/posts.php
+++ b/lang/pt-BR/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Adicionar :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Texto alternativo',
+            'edit' => 'Editar texto alternativo',
+            'placeholder' => 'Descreva esta imagem para pessoas que usam leitores de tela',
+            'hint' => 'Publicado nas plataformas que oferecem suporte a descrições de imagem.',
+            'badge' => 'ALT',
+            'save' => 'Salvar',
+        ],
+
         'emoji_picker' => [
             'search' => 'Buscar emoji',
             'empty' => 'Nenhum emoji encontrado',
diff --git a/lang/ru/posts.php b/lang/ru/posts.php
index 4042f461..4d101e1e 100644
--- a/lang/ru/posts.php
+++ b/lang/ru/posts.php
@@ -378,6 +378,15 @@
             'add_count' => 'Добавить :count',
         ],
 
+        'alt_text' => [
+            'label' => 'Альтернативный текст',
+            'edit' => 'Изменить альтернативный текст',
+            'placeholder' => 'Опишите это изображение для людей, использующих программы чтения с экрана',
+            'hint' => 'Публикуется на платформах, поддерживающих описания изображений.',
+            'badge' => 'ALT',
+            'save' => 'Сохранить',
+        ],
+
         'emoji_picker' => [
             'search' => 'Поиск эмодзи',
             'empty' => 'Эмодзи не найдены',
diff --git a/lang/tr/posts.php b/lang/tr/posts.php
index 8457a4ab..acba24a4 100644
--- a/lang/tr/posts.php
+++ b/lang/tr/posts.php
@@ -380,6 +380,15 @@
             'add_count' => ':count tane ekle',
         ],
 
+        'alt_text' => [
+            'label' => 'Alternatif metin',
+            'edit' => 'Alternatif metni düzenle',
+            'placeholder' => 'Ekran okuyucu kullanan kişiler için bu görseli açıklayın',
+            'hint' => 'Görsel açıklamalarını destekleyen platformlarda yayınlanır.',
+            'badge' => 'ALT',
+            'save' => 'Kaydet',
+        ],
+
         'emoji_picker' => [
             'search' => 'Emoji ara',
             'empty' => 'Emoji bulunamadı',
diff --git a/lang/zh/posts.php b/lang/zh/posts.php
index d490c1cc..81d23064 100644
--- a/lang/zh/posts.php
+++ b/lang/zh/posts.php
@@ -378,6 +378,15 @@
             'add_count' => '添加 :count 个',
         ],
 
+        'alt_text' => [
+            'label' => '替代文本',
+            'edit' => '编辑替代文本',
+            'placeholder' => '为使用屏幕阅读器的用户描述此图片',
+            'hint' => '发布到支持图片描述的平台。',
+            'badge' => 'ALT',
+            'save' => '保存',
+        ],
+
         'emoji_picker' => [
             'search' => '搜索表情',
             'empty' => '未找到表情',
diff --git a/resources/js/components/posts/editor/AltTextDialog.vue b/resources/js/components/posts/editor/AltTextDialog.vue
new file mode 100644
index 00000000..6e863ca2
--- /dev/null
+++ b/resources/js/components/posts/editor/AltTextDialog.vue
@@ -0,0 +1,64 @@
+<script setup lang="ts">
+import { ref, watch } from 'vue';
+
+import { Button } from '@/components/ui/button';
+import { Dialog, DialogContent, DialogDescription, DialogFooter, DialogHeader, DialogTitle } from '@/components/ui/dialog';
+import { Label } from '@/components/ui/label';
+import { Textarea } from '@/components/ui/textarea';
+import type { MediaItem } from '@/types/media';
+
+const props = defineProps<{
+    mediaItem: MediaItem | null;
+}>();
+
+const open = defineModel<boolean>('open', { required: true });
+
+const emit = defineEmits<{
+    (e: 'save', value: string): void;
+}>();
+
+const value = ref('');
+
+watch(open, (isOpen) => {
+    if (isOpen) {
+        value.value = props.mediaItem?.meta?.alt_text ?? '';
+    }
+});
+
+const save = () => {
+    emit('save', value.value);
+    open.value = false;
+};
+</script>
+
+<template>
+    <Dialog v-model:open="open">
+        <DialogContent class="sm:max-w-xl" data-testid="alt-text-dialog">
+            <DialogHeader>
+                <DialogTitle>{{ $t('posts.edit.alt_text.edit') }}</DialogTitle>
+                <DialogDescription>{{ $t('posts.edit.alt_text.hint') }}</DialogDescription>
+            </DialogHeader>
+
+            <div class="space-y-2">
+                <Label for="alt-text-input">{{ $t('posts.edit.alt_text.label') }}</Label>
+                <Textarea
+                    id="alt-text-input"
+                    v-model="value"
+                    :placeholder="$t('posts.edit.alt_text.placeholder')"
+                    rows="4"
+                    data-testid="alt-text-input"
+                />
+                <p class="text-right text-xs tabular-nums text-foreground/60">{{ value.length }}</p>
+            </div>
+
+            <DialogFooter>
+                <Button data-testid="alt-text-save" @click="save">
+                    {{ $t('posts.edit.alt_text.save') }}
+                </Button>
+                <Button variant="outline" @click="open = false">
+                    {{ $t('posts.edit.cancel') }}
+                </Button>
+            </DialogFooter>
+        </DialogContent>
+    </Dialog>
+</template>
diff --git a/resources/js/components/posts/editor/PostEditorComposer.vue b/resources/js/components/posts/editor/PostEditorComposer.vue
index 094dfdac..c190c6c6 100644
--- a/resources/js/components/posts/editor/PostEditorComposer.vue
+++ b/resources/js/components/posts/editor/PostEditorComposer.vue
@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import {
     IconAlertTriangle,
+    IconAlt,
     IconFileTypePdf,
     IconGripVertical,
     IconHash,
@@ -16,6 +17,7 @@ import { trans } from 'laravel-vue-i18n';
 import { computed, nextTick, ref } from 'vue';
 
 import ImagePreviewDialog from '@/components/ImagePreviewDialog.vue';
+import AltTextDialog from '@/components/posts/editor/AltTextDialog.vue';
 import EmojiPicker from '@/components/posts/EmojiPicker.vue';
 import MediaPickerDialog from '@/components/posts/MediaPickerDialog.vue';
 import SignaturesModal from '@/components/posts/SignaturesModal.vue';
@@ -24,7 +26,7 @@ import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/comp
 import { formatBytes } from '@/composables/useMedia';
 import { getPlatformLabel, getPlatformLogo } from '@/composables/usePlatformLogo';
 import date from '@/date';
-import { classify, isDocument, isVideo, MediaType } from '@/lib/mediaType';
+import { classify, isDocument, isImage, isVideo, MediaType } from '@/lib/mediaType';
 import type { MediaItem } from '@/types/media';
 
 interface Signature {
@@ -205,6 +207,32 @@ const onMediaKeydown = async (event: KeyboardEvent, index: number) => {
 
 const issueLabel = (reason: string): string => trans(`posts.form.warnings.${reason}`);
 const canRegenerateWithAi = (item: MediaItem): boolean => props.allowAiRegenerate && item.source === 'ai';
+
+const altDialogOpen = ref(false);
+const altDialogIndex = ref<number | null>(null);
+const altDialogItem = computed<MediaItem | null>(() =>
+    altDialogIndex.value !== null ? (media.value[altDialogIndex.value] ?? null) : null,
+);
+
+const openAltText = (index: number) => {
+    altDialogIndex.value = index;
+    altDialogOpen.value = true;
+};
+
+const setAltText = (index: number, alt: string): void => {
+    const next = [...media.value];
+    const trimmed = alt.trim();
+    next[index] = {
+        ...next[index],
+        meta: { ...(next[index].meta ?? {}), alt_text: trimmed || undefined },
+    };
+    media.value = next;
+};
+
+const onAltTextSave = (value: string): void => {
+    if (altDialogIndex.value === null) return;
+    setAltText(altDialogIndex.value, value);
+};
 </script>
 
 <template>
@@ -269,6 +297,13 @@ const canRegenerateWithAi = (item: MediaItem): boolean => props.allowAiRegenerat
                             >
                                 {{ formatBytes(item.size) }}
                             </span>
+                            <span
+                                v-if="isImage(item) && item.meta?.alt_text"
+                                class="inline-flex rounded-md bg-black/65 px-1.5 py-0.5 font-bold tracking-wider backdrop-blur-sm"
+                                data-testid="alt-text-badge"
+                            >
+                                {{ $t('posts.edit.alt_text.badge') }}
+                            </span>
                         </div>
 
                         <TooltipProvider v-if="mediaIssues[item.id]" :delay-duration="100">
@@ -308,6 +343,18 @@ const canRegenerateWithAi = (item: MediaItem): boolean => props.allowAiRegenerat
                             {{ $t('posts.ai.image_regenerate.button') }}
                         </button>
 
+                        <button
+                            v-if="!readOnly && isImage(item)"
+                            type="button"
+                            :title="$t('posts.edit.alt_text.edit')"
+                            :aria-label="$t('posts.edit.alt_text.edit')"
+                            class="absolute right-9 top-1.5 inline-flex size-6 cursor-pointer items-center justify-center rounded-md border-2 border-foreground bg-card text-foreground opacity-0 shadow-2xs transition-all hover:bg-violet-100 group-hover:opacity-100 group-focus:opacity-100"
+                            data-testid="alt-text-button"
+                            @click.stop="openAltText(index)"
+                        >
+                            <IconAlt class="size-3.5" />
+                        </button>
+
                         <button
                             v-if="!readOnly"
                             type="button"
@@ -449,5 +496,6 @@ const canRegenerateWithAi = (item: MediaItem): boolean => props.allowAiRegenerat
         <SignaturesModal ref="signaturesModal" :signatures="signatures" @select="appendSignature" />
         <MediaPickerDialog ref="mediaPickerDialog" @select="addMediaFromGallery" />
         <ImagePreviewDialog ref="lightbox" />
+        <AltTextDialog v-model:open="altDialogOpen" :media-item="altDialogItem" @save="onAltTextSave" />
     </div>
 </template>
diff --git a/resources/js/types/media.ts b/resources/js/types/media.ts
index 26e1cba5..4a8a4fff 100644
--- a/resources/js/types/media.ts
+++ b/resources/js/types/media.ts
@@ -16,5 +16,6 @@ export interface MediaItem {
         width?: number;
         height?: number;
         duration?: number;
+        alt_text?: string;
     };
 }