diff --git a/src/app/(app)/pdf/[id]/page.tsx b/src/app/(app)/pdf/[id]/page.tsx
index 52b6f9c..32abacf 100644
--- a/src/app/(app)/pdf/[id]/page.tsx
+++ b/src/app/(app)/pdf/[id]/page.tsx
@@ -10,6 +10,7 @@ import { DocumentHeaderMenu } from '@/components/documents/DocumentHeaderMenu';
 import { SegmentsSidebar } from '@/components/reader/SegmentsSidebar';
 import { Header } from '@/components/Header';
 import { AudiobookExportModal } from '@/components/AudiobookExportModal';
+import { ConfirmDialog } from '@/components/ConfirmDialog';
 import type { TTSAudiobookChapter } from '@/types/tts';
 import type { AudiobookGenerationSettings } from '@/types/client';
 import TTSPlayer from '@/components/player/TTSPlayer';
@@ -19,6 +20,12 @@ import { RateLimitBanner } from '@/components/auth/RateLimitBanner';
 import { useAuthRateLimit } from '@/contexts/AuthRateLimitContext';
 import { useFeatureFlag } from '@/contexts/RuntimeConfigContext';
 import { LoadingSpinner } from '@/components/Spinner';
+import {
+  FORCE_REPARSE_CONFIRM_MESSAGE,
+  FORCE_REPARSE_CONFIRM_TEXT,
+  FORCE_REPARSE_CONFIRM_TITLE,
+  isForceReparseDisabled,
+} from '@/lib/client/pdf/force-reparse';
 import { usePdfDocument } from './usePdfDocument';
 
 // Dynamic import for client-side rendering only
@@ -58,6 +65,7 @@ export default function PDFViewerPage() {
   const [isPdfViewerReady, setIsPdfViewerReady] = useState(false);
   const [zoomLevel, setZoomLevel] = useState<number>(100);
   const [activeSidebar, setActiveSidebar] = useState<null | 'settings' | 'audiobook' | 'segments'>(null);
+  const [showForceReparseConfirm, setShowForceReparseConfirm] = useState(false);
   const [containerHeight, setContainerHeight] = useState<string>('auto');
   const inFlightDocIdRef = useRef<string | null>(null);
   const loadedDocIdRef = useRef<string | null>(null);
@@ -66,6 +74,7 @@ export default function PDFViewerPage() {
   const [isNavigatingBack, setIsNavigatingBack] = useState(false);
   const parseState = parseStatus ?? 'pending';
   const isParseReady = parseState === 'ready';
+  const forceReparseDisabled = isForceReparseDisabled(parseStatus);
 
   useEffect(() => {
     setIsLoading(true);
@@ -198,6 +207,16 @@ export default function PDFViewerPage() {
     }, delayMs);
   }, [isNavigatingBack, stop, activeSidebar, router]);
 
+  const requestForceReparse = useCallback(() => {
+    if (forceReparseDisabled) return;
+    setShowForceReparseConfirm(true);
+  }, [forceReparseDisabled]);
+
+  const confirmForceReparse = useCallback(() => {
+    setShowForceReparseConfirm(false);
+    void forceReparseParsedPdf();
+  }, [forceReparseParsedPdf]);
+
   const handleGenerateAudiobook = useCallback(async (
     onProgress: (progress: number) => void,
     signal: AbortSignal,
@@ -339,7 +358,7 @@ export default function PDFViewerPage() {
               <div className="flex justify-start">
                 <button
                   type="button"
-                  onClick={() => forceReparseParsedPdf()}
+                  onClick={requestForceReparse}
                   className="inline-flex items-center rounded-md border border-offbase bg-offbase px-2.5 py-1 text-xs text-foreground hover:text-accent transition-colors"
                 >
                   Retry Parse
@@ -445,9 +464,18 @@ export default function PDFViewerPage() {
               },
             });
           },
-          onForceReparse: () => forceReparseParsedPdf(),
+          onForceReparse: requestForceReparse,
         }}
       />
+      <ConfirmDialog
+        isOpen={showForceReparseConfirm}
+        onClose={() => setShowForceReparseConfirm(false)}
+        onConfirm={confirmForceReparse}
+        title={FORCE_REPARSE_CONFIRM_TITLE}
+        message={FORCE_REPARSE_CONFIRM_MESSAGE}
+        confirmText={FORCE_REPARSE_CONFIRM_TEXT}
+        cancelText="Cancel"
+      />
       <SegmentsSidebar
         isOpen={activeSidebar === 'segments'}
         setIsOpen={(isOpen) => setActiveSidebar((prev) => isOpen ? 'segments' : (prev === 'segments' ? null : prev))}
diff --git a/src/components/documents/DocumentSettings.tsx b/src/components/documents/DocumentSettings.tsx
index 0516b02..510a996 100644
--- a/src/components/documents/DocumentSettings.tsx
+++ b/src/components/documents/DocumentSettings.tsx
@@ -18,6 +18,7 @@ import {
 import { Section, ToggleRow, CheckItem, buttonClass, segmentedButtonClass, segmentedGroupClass } from '@/components/formPrimitives';
 import { RefreshIcon, SparkleIcon } from '@/components/icons/Icons';
 import type { ParsedPdfBlockKind, PdfParseStatus } from '@/types/parsed-pdf';
+import { isForceReparseDisabled } from '@/lib/client/pdf/force-reparse';
 
 const PDF_SKIP_KIND_OPTIONS: Array<{ kind: ParsedPdfBlockKind; label: string }> = [
   { kind: 'header', label: 'Header' },
@@ -221,10 +222,10 @@ export function DocumentSettings({ isOpen, setIsOpen, epub, html, pdf }: {
                     type="button"
                     className={buttonClass({ variant: 'ghost', size: 'icon', className: '!h-5 !w-5 hover:scale-[1.1] shrink-0' })}
                     onClick={pdf.onForceReparse}
-                    disabled={pdf.parseStatus === 'running' || pdf.parseStatus === 'pending'}
+                    disabled={isForceReparseDisabled(pdf.parseStatus)}
                     title="Force reparse"
                   >
-                    <RefreshIcon className={`h-3 w-3 ${pdf.parseStatus === 'running' || pdf.parseStatus === 'pending' ? 'animate-spin' : ''}`} />
+                    <RefreshIcon className={`h-3 w-3 ${isForceReparseDisabled(pdf.parseStatus) ? 'animate-spin' : ''}`} />
                   </button>
                 </span>
               </div>
diff --git a/src/lib/client/pdf/force-reparse.ts b/src/lib/client/pdf/force-reparse.ts
new file mode 100644
index 0000000..425976d
--- /dev/null
+++ b/src/lib/client/pdf/force-reparse.ts
@@ -0,0 +1,9 @@
+import type { PdfParseStatus } from '@/types/parsed-pdf';
+
+export const FORCE_REPARSE_CONFIRM_TITLE = 'Reparse PDF Layout?';
+export const FORCE_REPARSE_CONFIRM_MESSAGE = 'This reruns page layout parsing from scratch and can take a while on large documents.';
+export const FORCE_REPARSE_CONFIRM_TEXT = 'Reparse Now';
+
+export function isForceReparseDisabled(status: PdfParseStatus | null): boolean {
+  return status === 'pending' || status === 'running';
+}
diff --git a/tests/unit/pdf-force-reparse.spec.ts b/tests/unit/pdf-force-reparse.spec.ts
new file mode 100644
index 0000000..95c2ce4
--- /dev/null
+++ b/tests/unit/pdf-force-reparse.spec.ts
@@ -0,0 +1,24 @@
+import { expect, test } from '@playwright/test';
+import {
+  FORCE_REPARSE_CONFIRM_MESSAGE,
+  FORCE_REPARSE_CONFIRM_TEXT,
+  FORCE_REPARSE_CONFIRM_TITLE,
+  isForceReparseDisabled,
+} from '../../src/lib/client/pdf/force-reparse';
+
+test.describe('pdf force reparse controls', () => {
+  test('disables action while parse is pending or running', () => {
+    expect(isForceReparseDisabled('pending')).toBeTruthy();
+    expect(isForceReparseDisabled('running')).toBeTruthy();
+    expect(isForceReparseDisabled('ready')).toBeFalsy();
+    expect(isForceReparseDisabled('failed')).toBeFalsy();
+    expect(isForceReparseDisabled(null)).toBeFalsy();
+  });
+
+  test('confirmation copy warns about expensive rerun', () => {
+    expect(FORCE_REPARSE_CONFIRM_TITLE).toContain('Reparse');
+    expect(FORCE_REPARSE_CONFIRM_TEXT).toContain('Reparse');
+    expect(FORCE_REPARSE_CONFIRM_MESSAGE.toLowerCase()).toContain('from scratch');
+    expect(FORCE_REPARSE_CONFIRM_MESSAGE.toLowerCase()).toContain('take a while');
+  });
+});