diff --git a/apps/dashboard/src/features/media/media-card.tsx b/apps/dashboard/src/features/media/media-card.tsx
index 1f14a21..1651f10 100644
--- a/apps/dashboard/src/features/media/media-card.tsx
+++ b/apps/dashboard/src/features/media/media-card.tsx
@@ -5,22 +5,22 @@ interface MediaCardProps {
   item: MediaItem;
   isRevealed: boolean;
   onToggleReveal(): void;
+  onOpenPreview(): void;
 }
 
 function formatMediaDate(timestamp: number): string {
   return new Intl.DateTimeFormat(undefined, { dateStyle: 'medium', timeStyle: 'short' }).format(timestamp);
 }
 
-export function MediaCard({ item, isRevealed, onToggleReveal }: MediaCardProps) {
+export function MediaCard({ item, isRevealed, onToggleReveal, onOpenPreview }: MediaCardProps) {
   return (
     <article className="media-card">
       <div className="media-preview">
-        <img
-          alt={`Media from ${item.sender}`}
-          className={isRevealed ? 'media-image' : 'media-image is-blurred'}
-          loading="lazy"
-          src={item.urlPath}
-        />
+        {isRevealed ? (
+          <button aria-label={`View media from ${item.sender} larger`} className="media-preview-button" onClick={onOpenPreview} type="button">
+            <img alt={`Media from ${item.sender}`} className="media-image" loading="lazy" src={item.urlPath} />
+          </button>
+        ) : <img alt={`Media from ${item.sender}`} className="media-image is-blurred" loading="lazy" src={item.urlPath} />}
         {!isRevealed ? <span className="privacy-label">Private media hidden</span> : null}
       </div>
       <div className="media-card-body">
diff --git a/apps/dashboard/src/features/media/media-page.tsx b/apps/dashboard/src/features/media/media-page.tsx
index ef2be5f..c8995dd 100644
--- a/apps/dashboard/src/features/media/media-page.tsx
+++ b/apps/dashboard/src/features/media/media-page.tsx
@@ -2,6 +2,7 @@ import { useMemo, useState } from 'react';
 import { filterMedia, mediaConversation, type MediaFilters } from './filters.js';
 import { FullSyncDialog } from './full-sync-dialog.js';
 import { MediaCard } from './media-card.js';
+import { MediaPreviewDialog } from './media-preview-dialog.js';
 import { useMediaQuery, useMediaSyncStatusQuery, useTriggerMediaSyncMutation } from './queries.js';
 import './media.css';
 
@@ -34,6 +35,7 @@ export function MediaPage({ filters: controlledFilters, onFiltersChange }: Media
   const [revealedIds, setRevealedIds] = useState<Set<string>>(() => new Set());
   const [isRevealAll, setIsRevealAll] = useState(false);
   const [isFullSyncDialogOpen, setIsFullSyncDialogOpen] = useState(false);
+  const [previewItemId, setPreviewItemId] = useState<string | null>(null);
 
   const items = mediaQuery.data ?? [];
   const visibleItems = useMemo(() => filterMedia(items, filters, Date.now()), [items, filters]);
@@ -46,6 +48,7 @@ export function MediaPage({ filters: controlledFilters, onFiltersChange }: Media
     [items],
   );
   const isSyncBusy = statusQuery.data?.isSyncing === true || syncMutation.isPending;
+  const previewItem = items.find((item) => item.id === previewItemId) ?? null;
 
   function updateFilter<Key extends keyof MediaFilters>(key: Key, value: MediaFilters[Key]) {
     const next = { ...filters, [key]: value };
@@ -196,6 +199,7 @@ export function MediaPage({ filters: controlledFilters, onFiltersChange }: Media
                   isRevealed={isRevealAll || revealedIds.has(item.id)}
                   item={item}
                   key={item.id}
+                  onOpenPreview={() => setPreviewItemId(item.id)}
                   onToggleReveal={() => toggleItem(item.id)}
                 />
               ))}
@@ -211,6 +215,7 @@ export function MediaPage({ filters: controlledFilters, onFiltersChange }: Media
           onConfirm={() => runSync(true)}
         />
       ) : null}
+      {previewItem ? <MediaPreviewDialog item={previewItem} onClose={() => setPreviewItemId(null)} /> : null}
     </div>
   );
 }
diff --git a/apps/dashboard/src/features/media/media-preview-dialog.tsx b/apps/dashboard/src/features/media/media-preview-dialog.tsx
new file mode 100644
index 0000000..3864755
--- /dev/null
+++ b/apps/dashboard/src/features/media/media-preview-dialog.tsx
@@ -0,0 +1,37 @@
+import { useEffect, useRef } from 'react';
+import type { MediaItem } from '../../../../../packages/api-contracts/src/index.js';
+
+interface MediaPreviewDialogProps {
+  item: MediaItem;
+  onClose(): void;
+}
+
+export function MediaPreviewDialog({ item, onClose }: MediaPreviewDialogProps) {
+  const closeButtonRef = useRef<HTMLButtonElement>(null);
+
+  useEffect(() => {
+    closeButtonRef.current?.focus();
+    function handleKeyDown(event: KeyboardEvent) {
+      if (event.key === 'Escape') onClose();
+    }
+    document.addEventListener('keydown', handleKeyDown);
+    return () => document.removeEventListener('keydown', handleKeyDown);
+  }, [onClose]);
+
+  return (
+    <div
+      aria-label={`Media from ${item.sender}`}
+      aria-modal="true"
+      className="media-preview-dialog-backdrop"
+      onClick={(event) => {
+        if (event.target === event.currentTarget) onClose();
+      }}
+      role="dialog"
+    >
+      <div className="media-preview-dialog-content">
+        <img alt={`Media from ${item.sender}`} className="media-preview-dialog-image" src={item.urlPath} />
+        <button aria-label="Close media preview" className="media-preview-dialog-close" onClick={onClose} ref={closeButtonRef} type="button">×</button>
+      </div>
+    </div>
+  );
+}
diff --git a/apps/dashboard/src/features/media/media.css b/apps/dashboard/src/features/media/media.css
index 0380a9a..d982402 100644
--- a/apps/dashboard/src/features/media/media.css
+++ b/apps/dashboard/src/features/media/media.css
@@ -12,6 +12,8 @@
 .media-grid { display: grid; grid-template-columns: 1fr; gap: 1rem; }
 .media-card { min-width: 0; overflow: hidden; background: var(--surface); border: 1px solid var(--border); border-radius: .9rem; }
 .media-preview { position: relative; display: grid; place-items: center; aspect-ratio: 4 / 3; overflow: hidden; background: #050907; }
+.media-preview-button { width: 100%; height: 100%; padding: 0; border: 0; background: transparent; cursor: zoom-in; }
+.media-preview-button:focus-visible { outline: 2px solid var(--accent); outline-offset: -4px; }
 .media-image { width: 100%; height: 100%; object-fit: cover; transition: filter 160ms ease, transform 160ms ease; }
 .media-image.is-blurred { filter: blur(24px) brightness(.55); transform: scale(1.12); }
 .privacy-label { position: absolute; padding: .45rem .65rem; color: white; background: rgba(0, 0, 0, .72); border-radius: 999px; font-size: .75rem; font-weight: 800; }
@@ -23,6 +25,11 @@
 .media-card-body dt { color: var(--muted); }
 .media-card-body dd { margin: 0; text-align: right; }
 .media-reveal { width: 100%; }
+.media-preview-dialog-backdrop { position: fixed; inset: 0; z-index: 70; display: grid; place-items: center; padding: 1rem; background: rgba(0, 0, 0, .88); }
+.media-preview-dialog-content { position: relative; display: grid; place-items: center; width: min(100%, 90rem); height: min(100%, 90rem); }
+.media-preview-dialog-image { display: block; max-width: 100%; max-height: 100%; object-fit: contain; }
+.media-preview-dialog-close { position: absolute; top: .5rem; right: .5rem; width: 2.75rem; height: 2.75rem; padding: 0; border: 1px solid rgba(255, 255, 255, .5); border-radius: 50%; color: white; background: rgba(0, 0, 0, .7); font-size: 2rem; line-height: 1; cursor: pointer; }
+.media-preview-dialog-close:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
 
 @media (min-width: 40rem) {
   .media-filters { grid-template-columns: repeat(2, minmax(0, 1fr)); }
diff --git a/tests/dashboard/media.test.tsx b/tests/dashboard/media.test.tsx
index 5f5149c..f3a3a95 100644
--- a/tests/dashboard/media.test.tsx
+++ b/tests/dashboard/media.test.tsx
@@ -106,6 +106,21 @@ describe('media page', () => {
     expect(await screen.findByRole('img', { name: 'Media from alice' })).toHaveClass('is-blurred');
   });
 
+  it('opens revealed media in a dismissible full-size preview', async () => {
+    installMediaApi();
+    const user = userEvent.setup();
+    renderMedia();
+
+    await user.click(await screen.findByRole('button', { name: 'Reveal media from alice' }));
+    await user.click(screen.getByRole('button', { name: 'View media from alice larger' }));
+
+    const dialog = screen.getByRole('dialog', { name: 'Media from alice' });
+    expect(within(dialog).getByRole('img', { name: 'Media from alice' })).toHaveAttribute('src', '/media/one.jpg');
+
+    await user.keyboard('{Escape}');
+    expect(screen.queryByRole('dialog', { name: 'Media from alice' })).not.toBeInTheDocument();
+  });
+
   it('filters by conversation, sender, media type, and age with an explicit no-match state', async () => {
     installMediaApi();
     const user = userEvent.setup();