diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/ThumbnailService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/ThumbnailService.java
index 8fbf8d92..620a36c8 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/service/ThumbnailService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/ThumbnailService.java
@@ -86,20 +86,21 @@ public class ThumbnailService {
             return Outcome.SKIPPED;
         }
 
-        BufferedImage source = readSourceImage(doc, contentType);
-        if (source == null || source.getWidth() <= 0 || source.getHeight() <= 0) {
+        SourcePreview preview = readSourcePreview(doc, contentType);
+        if (preview == null
+                || preview.image().getWidth() <= 0 || preview.image().getHeight() <= 0) {
             log.warn("Thumbnail source has invalid dimensions for doc={}", doc.getId());
             return Outcome.FAILED;
         }
 
-        byte[] jpeg = encodeThumbnail(source, doc.getId());
+        byte[] jpeg = encodeThumbnail(preview.image(), doc.getId());
         if (jpeg == null) return Outcome.FAILED;
 
         String thumbnailKey = thumbnailKeyFor(doc.getId());
         if (!uploadToStorage(thumbnailKey, jpeg, doc.getId())) return Outcome.FAILED;
 
-        ThumbnailAspect aspect = aspectOf(source);
-        return persistThumbnailMetadata(doc, thumbnailKey, aspect);
+        ThumbnailAspect aspect = aspectOf(preview.image());
+        return persistThumbnailMetadata(doc, thumbnailKey, aspect, preview.pageCount());
     }
 
     private static ThumbnailAspect aspectOf(BufferedImage source) {
@@ -107,15 +108,19 @@ public class ThumbnailService {
         return ratio > LANDSCAPE_THRESHOLD ? ThumbnailAspect.LANDSCAPE : ThumbnailAspect.PORTRAIT;
     }
 
+    // First-page image + total page count for the source file. Page count is always
+    // 1 for image uploads; for PDFs it comes straight from PDDocument.
+    private record SourcePreview(BufferedImage image, int pageCount) {}
+
     private static String thumbnailKeyFor(UUID documentId) {
         return THUMBNAIL_KEY_PREFIX + documentId + THUMBNAIL_KEY_SUFFIX;
     }
 
-    private BufferedImage readSourceImage(Document doc, String contentType) {
+    private SourcePreview readSourcePreview(Document doc, String contentType) {
         try {
             return PDF_CONTENT_TYPE.equals(contentType)
                     ? renderPdfFirstPage(doc.getFilePath())
-                    : readImage(doc.getFilePath());
+                    : new SourcePreview(readImage(doc.getFilePath()), 1);
         } catch (Exception e) {
             log.warn("Thumbnail source read failed for doc={} reason={}",
                     doc.getId(), e.getMessage());
@@ -151,11 +156,13 @@ public class ThumbnailService {
         }
     }
 
-    private Outcome persistThumbnailMetadata(Document doc, String thumbnailKey, ThumbnailAspect aspect) {
+    private Outcome persistThumbnailMetadata(Document doc, String thumbnailKey,
+                                             ThumbnailAspect aspect, int pageCount) {
         try {
             doc.setThumbnailKey(thumbnailKey);
             doc.setThumbnailGeneratedAt(LocalDateTime.now());
             doc.setThumbnailAspect(aspect);
+            doc.setPageCount(pageCount);
             documentRepository.save(doc);
             return Outcome.SUCCESS;
         } catch (Exception e) {
@@ -174,11 +181,12 @@ public class ThumbnailService {
         return PDF_CONTENT_TYPE.equals(contentType) || IMAGE_CONTENT_TYPES.contains(contentType);
     }
 
-    private BufferedImage renderPdfFirstPage(String s3Key) throws IOException {
+    private SourcePreview renderPdfFirstPage(String s3Key) throws IOException {
         try (InputStream in = fileService.downloadFileStream(s3Key);
              PDDocument pdf = Loader.loadPDF(new RandomAccessReadBuffer(in))) {
             PDFRenderer renderer = new PDFRenderer(pdf);
-            return renderer.renderImageWithDPI(0, PDF_RENDER_DPI, ImageType.RGB);
+            BufferedImage image = renderer.renderImageWithDPI(0, PDF_RENDER_DPI, ImageType.RGB);
+            return new SourcePreview(image, pdf.getNumberOfPages());
         }
     }
 
diff --git a/backend/src/test/java/org/raddatz/familienarchiv/service/ThumbnailServiceTest.java b/backend/src/test/java/org/raddatz/familienarchiv/service/ThumbnailServiceTest.java
index df1f62b0..ad423401 100644
--- a/backend/src/test/java/org/raddatz/familienarchiv/service/ThumbnailServiceTest.java
+++ b/backend/src/test/java/org/raddatz/familienarchiv/service/ThumbnailServiceTest.java
@@ -168,6 +168,31 @@ class ThumbnailServiceTest {
         verify(documentRepository, never()).save(any());
     }
 
+    @Test
+    void generate_persistsPageCount_ofOne_forSingleImageUpload() throws IOException {
+        // Image uploads are always a single page from the user's perspective.
+        Document doc = makeDoc("image/png", "documents/scan.png");
+        when(fileService.downloadFileStream(anyString()))
+                .thenReturn(new ByteArrayInputStream(createSamplePng(600, 800)));
+
+        ThumbnailService.Outcome outcome = thumbnailService.generate(doc);
+
+        assertThat(outcome).isEqualTo(ThumbnailService.Outcome.SUCCESS);
+        assertThat(doc.getPageCount()).isEqualTo(1);
+    }
+
+    @Test
+    void generate_persistsPageCount_fromPdfDocument() throws IOException {
+        Document doc = makeDoc("application/pdf", "documents/multi.pdf");
+        when(fileService.downloadFileStream(anyString()))
+                .thenReturn(new ByteArrayInputStream(createSamplePdf(3)));
+
+        ThumbnailService.Outcome outcome = thumbnailService.generate(doc);
+
+        assertThat(outcome).isEqualTo(ThumbnailService.Outcome.SUCCESS);
+        assertThat(doc.getPageCount()).isEqualTo(3);
+    }
+
     @Test
     void generate_persistsPortraitAspect_forTypicalPortraitSourceImage() throws IOException {
         // 600x800 → ratio w/h = 0.75 → below 1.1 threshold → PORTRAIT.
@@ -288,15 +313,21 @@ class ThumbnailServiceTest {
     }
 
     private static byte[] createSamplePdf() throws IOException {
+        return createSamplePdf(1);
+    }
+
+    private static byte[] createSamplePdf(int pageCount) throws IOException {
         try (PDDocument doc = new PDDocument()) {
-            PDPage page = new PDPage(PDRectangle.A4);
-            doc.addPage(page);
-            try (PDPageContentStream content = new PDPageContentStream(doc, page)) {
-                content.beginText();
-                content.setFont(new PDType1Font(Standard14Fonts.FontName.HELVETICA), 24);
-                content.newLineAtOffset(100, 700);
-                content.showText("Lieber Hans,");
-                content.endText();
+            for (int i = 0; i < pageCount; i++) {
+                PDPage page = new PDPage(PDRectangle.A4);
+                doc.addPage(page);
+                try (PDPageContentStream content = new PDPageContentStream(doc, page)) {
+                    content.beginText();
+                    content.setFont(new PDType1Font(Standard14Fonts.FontName.HELVETICA), 24);
+                    content.newLineAtOffset(100, 700);
+                    content.showText("Lieber Hans,");
+                    content.endText();
+                }
             }
             ByteArrayOutputStream bos = new ByteArrayOutputStream();
             doc.save(bos);