diff --git a/apps/backoffice/app/books/[id]/page.tsx b/apps/backoffice/app/books/[id]/page.tsx
index 23c907d..0b7286b 100644
--- a/apps/backoffice/app/books/[id]/page.tsx
+++ b/apps/backoffice/app/books/[id]/page.tsx
@@ -120,9 +120,12 @@ export default async function BookDetailPage({
               <div className="flex items-center justify-between py-2 border-b border-border">
                 <span className="text-sm text-muted-foreground">Format:</span>
                 <span className={`inline-flex px-2.5 py-1 rounded-full text-xs font-semibold ${
-                  book.kind === 'epub' ? 'bg-primary/10 text-primary' : 'bg-muted/50 text-muted-foreground'
+                  (book.format ?? book.kind) === 'cbz' ? 'bg-success/10 text-success' :
+                  (book.format ?? book.kind) === 'cbr' ? 'bg-warning/10 text-warning' :
+                  (book.format ?? book.kind) === 'pdf' ? 'bg-destructive/10 text-destructive' :
+                  'bg-muted/50 text-muted-foreground'
                 }`}>
-                  {book.kind.toUpperCase()}
+                  {(book.format ?? book.kind).toUpperCase()}
                 </span>
               </div>
               
diff --git a/apps/backoffice/app/books/page.tsx b/apps/backoffice/app/books/page.tsx
index 78b344d..0da44f8 100644
--- a/apps/backoffice/app/books/page.tsx
+++ b/apps/backoffice/app/books/page.tsx
@@ -44,6 +44,7 @@ export default async function BooksPage({
         volume: hit.volume,
         language: hit.language,
         page_count: null,
+        format: null,
         file_path: null,
         file_format: null,
         file_parse_status: null,
diff --git a/apps/backoffice/app/components/BookCard.tsx b/apps/backoffice/app/components/BookCard.tsx
index 3d1f886..f4f1dff 100644
--- a/apps/backoffice/app/components/BookCard.tsx
+++ b/apps/backoffice/app/components/BookCard.tsx
@@ -102,14 +102,16 @@ export function BookCard({ book, readingStatus }: BookCardProps) {
         
         {/* Meta Tags */}
         <div className="flex items-center gap-2 mt-2">
-          <span className={`
-            px-2 py-0.5 text-[10px] font-bold uppercase tracking-wider rounded-full
-            ${book.kind === 'cbz' ? 'bg-success/10 text-success' : ''}
-            ${book.kind === 'cbr' ? 'bg-warning/10 text-warning' : ''}
-            ${book.kind === 'pdf' ? 'bg-destructive/10 text-destructive' : ''}
-          `}>
-            {book.kind}
-          </span>
+          {(book.format ?? book.kind) && (
+            <span className={`
+              px-2 py-0.5 text-[10px] font-bold uppercase tracking-wider rounded-full
+              ${(book.format ?? book.kind) === 'cbz' ? 'bg-success/10 text-success' : ''}
+              ${(book.format ?? book.kind) === 'cbr' ? 'bg-warning/10 text-warning' : ''}
+              ${(book.format ?? book.kind) === 'pdf' ? 'bg-destructive/10 text-destructive' : ''}
+            `}>
+              {book.format ?? book.kind}
+            </span>
+          )}
           {book.language && (
             <span className="px-2 py-0.5 text-[10px] font-medium uppercase tracking-wider rounded-full bg-primary/10 text-primary">
               {book.language}
diff --git a/apps/backoffice/lib/api.ts b/apps/backoffice/lib/api.ts
index 67dd5ce..93c7a4f 100644
--- a/apps/backoffice/lib/api.ts
+++ b/apps/backoffice/lib/api.ts
@@ -59,6 +59,7 @@ export type BookDto = {
   id: string;
   library_id: string;
   kind: string;
+  format: string | null;
   title: string;
   author: string | null;
   series: string | null;