diff --git a/apps/web/src/pages/ReaderPage.tsx b/apps/web/src/pages/ReaderPage.tsx
index de88794..aa2adfa 100644
--- a/apps/web/src/pages/ReaderPage.tsx
+++ b/apps/web/src/pages/ReaderPage.tsx
@@ -41,6 +41,7 @@ export function ReaderPage({ bookId }: { bookId: number }) {
   }, [progress]);
 
   const fileUrl = useMemo(() => api.bookFileUrl(bookId), [bookId]);
+  const backHref = useMemo(() => (book ? `/book/${book.id}` : "/home"), [book]);
   const savePdfPage = useCallback(
     (nextPage: number, pages: number) => {
       setPage(nextPage);
@@ -61,7 +62,7 @@ export function ReaderPage({ bookId }: { bookId: number }) {
   return (
     <div className="reader-page">
       <header className="reader-topbar">
-        <button className="ghost-button" onClick={() => navigate(book ? `/book/${book.id}` : "/home")}>
+        <button className="ghost-button" onClick={() => navigate(backHref)}>
           <ArrowLeft size={17} />
           Fiche
         </button>
@@ -87,11 +88,11 @@ export function ReaderPage({ bookId }: { bookId: number }) {
           </button>
         </div>
       ) : book.format === "pdf" ? (
-        <PdfReader url={fileUrl} page={page} onPageCommit={savePdfPage} />
+        <PdfReader url={fileUrl} page={page} backHref={backHref} onPageCommit={savePdfPage} />
       ) : book.format === "cbz" || book.format === "cbr" ? (
         <CbzReader bookId={book.id} page={page} onPageCommit={saveComicPage} />
       ) : (
-        <EpubReader url={fileUrl} locator={progress?.locator} onLocatorChange={saveEpubLocator} />
+        <EpubReader url={fileUrl} locator={progress?.locator} backHref={backHref} onLocatorChange={saveEpubLocator} />
       )}
     </div>
   );
diff --git a/apps/web/src/reader/EpubReader.tsx b/apps/web/src/reader/EpubReader.tsx
index 3b16cb1..2c089f3 100644
--- a/apps/web/src/reader/EpubReader.tsx
+++ b/apps/web/src/reader/EpubReader.tsx
@@ -1,43 +1,145 @@
 import { useEffect, useRef, useState } from "react";
+import { ArrowLeft, ArrowRight } from "lucide-react";
+import { ReaderError, readerErrorMessage } from "./ReaderError";
 
-type FoliateModule = {
-  EPUB?: unknown;
-  default?: unknown;
+type FoliateLocation = {
+  cfi?: string;
+  fraction?: number;
+  current?: number;
+  total?: number;
 };
 
-export function EpubReader({ url, locator, onLocatorChange }: { url: string; locator?: string; onLocatorChange: (locator: string, percent: number) => void }) {
+type FoliateView = HTMLElement & {
+  open(input: File | Blob | string): Promise<void>;
+  close(): void;
+  goLeft(): Promise<void>;
+  goRight(): Promise<void>;
+  goTo(target: string): Promise<unknown>;
+  next(): Promise<void>;
+  lastLocation?: FoliateLocation;
+};
+
+export function epubFileName(url: string): string {
+  try {
+    const base = globalThis.location?.href ?? "http://readabook.local/";
+    const pathname = new URL(url, base).pathname;
+    const name = pathname.split("/").filter(Boolean).at(-1);
+    return name && name.includes(".") ? name : "book.epub";
+  } catch {
+    return "book.epub";
+  }
+}
+
+function locationPercent(location: FoliateLocation): number {
+  if (typeof location.fraction === "number") return Math.max(0, Math.min(100, location.fraction * 100));
+  if (typeof location.current === "number" && typeof location.total === "number" && location.total > 0) {
+    return Math.max(0, Math.min(100, (location.current / location.total) * 100));
+  }
+  return 1;
+}
+
+export function EpubReader({
+  url,
+  locator,
+  backHref,
+  onLocatorChange
+}: {
+  url: string;
+  locator?: string;
+  backHref: string;
+  onLocatorChange: (locator: string, percent: number) => void;
+}) {
   const hostRef = useRef<HTMLDivElement>(null);
-  const [frameKey, setFrameKey] = useState(0);
-  const [status, setStatus] = useState("Ouverture EPUB");
+  const viewRef = useRef<FoliateView | null>(null);
+  const locatorRef = useRef(locator);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string>();
+  const [attempt, setAttempt] = useState(0);
+
+  useEffect(() => {
+    locatorRef.current = locator;
+  }, [locator]);
 
   useEffect(() => {
     let cancelled = false;
+    let view: FoliateView | null = null;
+
     async function mount() {
       try {
-        const module = (await import("foliate-js/epub.js")) as FoliateModule;
+        setLoading(true);
+        setError(undefined);
+        await import("foliate-js/view.js");
         if (cancelled || !hostRef.current) return;
-        hostRef.current.dataset.engine = module.EPUB || module.default ? "foliate-js" : "fallback";
-        setStatus("EPUB pret");
-      } catch {
-        setStatus("Apercu EPUB indisponible dans ce navigateur");
+
+        const response = await fetch(url, { credentials: "include" });
+        if (!response.ok) throw new Error(`${response.status} ${response.statusText}`);
+        const blob = await response.blob();
+        if (cancelled || !hostRef.current) return;
+
+        view = document.createElement("foliate-view") as FoliateView;
+        view.classList.add("epub-view");
+        view.addEventListener("relocate", (event) => {
+          const location = (event as CustomEvent<FoliateLocation>).detail;
+          if (location?.cfi) onLocatorChange(location.cfi, locationPercent(location));
+        });
+        hostRef.current.replaceChildren(view);
+        viewRef.current = view;
+
+        const file = new File([blob], epubFileName(url), { type: blob.type || "application/epub+zip" });
+        await view.open(file);
+        if (cancelled) return;
+        if (locatorRef.current) await view.goTo(locatorRef.current);
+        else await view.next();
+        setLoading(false);
+      } catch (mountError) {
+        if (!cancelled) {
+          setError(readerErrorMessage(mountError, "EPUB indisponible"));
+          setLoading(false);
+        }
       }
     }
-    mount();
+
+    void mount();
     return () => {
       cancelled = true;
+      view?.close?.();
+      view?.remove();
+      if (viewRef.current === view) viewRef.current = null;
     };
-  }, [url]);
+  }, [attempt, onLocatorChange, url]);
+
+  if (error) {
+    return (
+      <div className="epub-reader">
+        <ReaderError
+          title="Lecture EPUB indisponible"
+          detail="ReadaBook n'a pas pu ouvrir ce fichier dans le lecteur web."
+          technicalDetail={error}
+          downloadUrl={url}
+          backHref={backHref}
+          onRetry={() => setAttempt((value) => value + 1)}
+        />
+      </div>
+    );
+  }
 
   return (
-    <div className="epub-reader" ref={hostRef}>
-      <iframe key={frameKey} title="EPUB" src={url} />
-      <div className="reader-fallback">
-        <span>{status}</span>
-        <button className="ghost-button" onClick={() => onLocatorChange(locator ?? "epub:start", locator ? 35 : 1)}>
-          Marquer la position
+    <div className="epub-reader">
+      {loading && (
+        <div className="reader-fallback">
+          <span>Ouverture EPUB</span>
+        </div>
+      )}
+      <div className="epub-host" ref={hostRef} />
+      <div className="reader-stepper">
+        <button className="ghost-button" onClick={() => void viewRef.current?.goLeft()} disabled={loading}>
+          <ArrowLeft size={16} />
+          Précédent
         </button>
-        <button className="ghost-button" onClick={() => setFrameKey((value) => value + 1)}>
-          Recharger
+        <span>{loading ? "Chargement" : "Lecture intégrée"}</span>
+        <button className="ghost-button" onClick={() => void viewRef.current?.goRight()} disabled={loading}>
+          Suivant
+          <ArrowRight size={16} />
         </button>
       </div>
     </div>
diff --git a/apps/web/src/reader/PdfReader.tsx b/apps/web/src/reader/PdfReader.tsx
index 4dae444..42cf30d 100644
--- a/apps/web/src/reader/PdfReader.tsx
+++ b/apps/web/src/reader/PdfReader.tsx
@@ -1,21 +1,36 @@
 import { useEffect, useRef, useState } from "react";
 import * as pdfjs from "pdfjs-dist";
-import workerUrl from "pdfjs-dist/build/pdf.worker.mjs?url";
+import { ReaderError, readerErrorMessage } from "./ReaderError";
+import { pdfWorkerSrc } from "./pdfWorker";
 
-pdfjs.GlobalWorkerOptions.workerSrc = workerUrl;
+pdfjs.GlobalWorkerOptions.workerSrc = pdfWorkerSrc;
 
-export function PdfReader({ url, page, onPageCommit }: { url: string; page: number; onPageCommit: (page: number, pages: number) => void }) {
+export function PdfReader({
+  url,
+  page,
+  backHref,
+  onPageCommit
+}: {
+  url: string;
+  page: number;
+  backHref: string;
+  onPageCommit: (page: number, pages: number) => void;
+}) {
   const canvasRef = useRef<HTMLCanvasElement>(null);
   const [pages, setPages] = useState(1);
   const [error, setError] = useState<string>();
+  const [loading, setLoading] = useState(true);
   const [attempt, setAttempt] = useState(0);
 
   useEffect(() => {
     let cancelled = false;
+    let loadingTask: pdfjs.PDFDocumentLoadingTask | undefined;
+    let renderTask: pdfjs.RenderTask | undefined;
     async function render() {
       try {
+        setLoading(true);
         setError(undefined);
-        const loadingTask = pdfjs.getDocument({ url, withCredentials: true });
+        loadingTask = pdfjs.getDocument({ url, withCredentials: true });
         const document = await loadingTask.promise;
         if (cancelled) return;
         setPages(document.numPages);
@@ -27,37 +42,53 @@ export function PdfReader({ url, page, onPageCommit }: { url: string; page: numb
         canvas.height = viewport.height;
         const context = canvas.getContext("2d");
         if (!context) return;
-        await pdfPage.render({ canvas, canvasContext: context, viewport }).promise;
+        renderTask = pdfPage.render({ canvas, canvasContext: context, viewport });
+        await renderTask.promise;
+        if (!cancelled) setLoading(false);
       } catch (renderError) {
-        setError(renderError instanceof Error ? renderError.message : "PDF indisponible");
+        if (!cancelled) {
+          setError(readerErrorMessage(renderError, "PDF indisponible"));
+          setLoading(false);
+        }
       }
     }
-    render();
+    void render();
     return () => {
       cancelled = true;
+      renderTask?.cancel();
+      void loadingTask?.destroy();
     };
   }, [url, page, attempt]);
 
   return (
     <div className="pdf-reader">
       {error ? (
-        <div className="reader-fallback">
-          <span>{error}</span>
-          <button className="ghost-button" onClick={() => setAttempt((value) => value + 1)}>
-            Reessayer
-          </button>
-        </div>
+        <ReaderError
+          title="Lecture PDF indisponible"
+          detail="ReadaBook n'a pas pu ouvrir ce fichier dans le lecteur web."
+          technicalDetail={error}
+          downloadUrl={url}
+          backHref={backHref}
+          onRetry={() => setAttempt((value) => value + 1)}
+        />
       ) : (
-        <canvas ref={canvasRef} />
+        <>
+          {loading && (
+            <div className="reader-fallback">
+              <span>Ouverture PDF</span>
+            </div>
+          )}
+          <canvas ref={canvasRef} />
+        </>
       )}
       <div className="reader-stepper">
-        <button className="ghost-button" onClick={() => onPageCommit(Math.max(1, page - 1), pages)}>
-          Precedent
+        <button className="ghost-button" onClick={() => onPageCommit(Math.max(1, page - 1), pages)} disabled={Boolean(error) || loading}>
+          Précédent
         </button>
         <span>
           {page} / {pages}
         </span>
-        <button className="ghost-button" onClick={() => onPageCommit(Math.min(pages, page + 1), pages)}>
+        <button className="ghost-button" onClick={() => onPageCommit(Math.min(pages, page + 1), pages)} disabled={Boolean(error) || loading}>
           Suivant
         </button>
       </div>
diff --git a/apps/web/src/reader/ReaderError.tsx b/apps/web/src/reader/ReaderError.tsx
new file mode 100644
index 0000000..7a184de
--- /dev/null
+++ b/apps/web/src/reader/ReaderError.tsx
@@ -0,0 +1,53 @@
+import { ArrowLeft, Download, RotateCcw } from "lucide-react";
+import { navigate } from "../router";
+
+export function readerErrorMessage(error: unknown, fallback: string): string {
+  if (error instanceof Error && error.message.trim()) return error.message;
+  if (typeof error === "string" && error.trim()) return error;
+  return fallback;
+}
+
+export function ReaderError({
+  title,
+  detail,
+  technicalDetail,
+  downloadUrl,
+  backHref,
+  onRetry
+}: {
+  title: string;
+  detail: string;
+  technicalDetail?: string;
+  downloadUrl: string;
+  backHref: string;
+  onRetry: () => void;
+}) {
+  return (
+    <div className="reader-error">
+      <div>
+        <h2>{title}</h2>
+        <p>{detail}</p>
+      </div>
+      <div className="reader-error-actions">
+        <button className="ghost-button" onClick={onRetry}>
+          <RotateCcw size={16} />
+          Réessayer
+        </button>
+        <button className="ghost-button" onClick={() => navigate(backHref)}>
+          <ArrowLeft size={16} />
+          Retour à la fiche
+        </button>
+        <a className="ghost-button" href={downloadUrl} download>
+          <Download size={16} />
+          Télécharger
+        </a>
+      </div>
+      {technicalDetail && (
+        <details>
+          <summary>Détail technique</summary>
+          <pre>{technicalDetail}</pre>
+        </details>
+      )}
+    </div>
+  );
+}
diff --git a/apps/web/src/reader/pdfWorker.ts b/apps/web/src/reader/pdfWorker.ts
new file mode 100644
index 0000000..54cdf6d
--- /dev/null
+++ b/apps/web/src/reader/pdfWorker.ts
@@ -0,0 +1 @@
+export const pdfWorkerSrc = new URL("pdfjs-dist/build/pdf.worker.min.mjs", import.meta.url).toString();
diff --git a/apps/web/src/reader/readerRuntime.test.ts b/apps/web/src/reader/readerRuntime.test.ts
new file mode 100644
index 0000000..87df2c5
--- /dev/null
+++ b/apps/web/src/reader/readerRuntime.test.ts
@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { epubFileName } from "./EpubReader";
+import { pdfWorkerSrc } from "./pdfWorker";
+import { readerErrorMessage } from "./ReaderError";
+
+describe("reader runtime helpers", () => {
+  it("extracts an EPUB file name from the file URL", () => {
+    expect(epubFileName("http://readabook.local/books/12/file?token=abc")).toBe("book.epub");
+    expect(epubFileName("http://readabook.local/files/example.epub")).toBe("example.epub");
+  });
+
+  it("keeps PDF.js worker source on the bundled module worker", () => {
+    expect(pdfWorkerSrc).toContain("pdf.worker.min.mjs");
+  });
+
+  it("normalizes reader technical errors", () => {
+    expect(readerErrorMessage(new Error("Setting up fake worker failed"), "PDF indisponible")).toBe("Setting up fake worker failed");
+    expect(readerErrorMessage("", "EPUB indisponible")).toBe("EPUB indisponible");
+  });
+});
diff --git a/apps/web/src/styles/app.css b/apps/web/src/styles/app.css
index 7fc8fe0..ec74de5 100644
--- a/apps/web/src/styles/app.css
+++ b/apps/web/src/styles/app.css
@@ -676,8 +676,23 @@ select {
   min-height: calc(100vh - 120px);
 }
 
+.epub-host {
+  display: grid;
+  width: min(100%, 980px);
+  height: calc(100vh - 170px);
+  min-height: 460px;
+}
+
+.epub-view {
+  width: 100%;
+  height: 100%;
+  border: 1px solid var(--line);
+  border-radius: var(--radius);
+  background: #f7f0df;
+  color: #17110d;
+}
+
 .pdf-reader canvas,
-.epub-reader iframe,
 .cbz-reader img {
   max-width: min(100%, 980px);
   max-height: calc(100vh - 170px);
@@ -691,11 +706,6 @@ select {
   object-fit: contain;
 }
 
-.epub-reader iframe {
-  width: min(100%, 980px);
-  height: calc(100vh - 170px);
-}
-
 .reader-fallback {
   display: flex;
   flex-wrap: wrap;
@@ -712,6 +722,46 @@ select {
   gap: 12px;
 }
 
+.reader-error {
+  display: grid;
+  gap: 14px;
+  width: min(100%, 620px);
+  padding: 18px;
+  border: 1px solid rgba(169, 72, 52, 0.72);
+  border-radius: var(--radius);
+  background: rgba(169, 72, 52, 0.14);
+}
+
+.reader-error p {
+  margin-bottom: 0;
+  color: var(--ink-muted);
+}
+
+.reader-error-actions {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 8px;
+}
+
+.reader-error a {
+  text-decoration: none;
+}
+
+.reader-error details {
+  color: var(--ink-muted);
+}
+
+.reader-error summary {
+  cursor: pointer;
+}
+
+.reader-error pre {
+  overflow: auto;
+  max-width: 100%;
+  margin: 10px 0 0;
+  white-space: pre-wrap;
+}
+
 @keyframes spin {
   to {
     transform: rotate(360deg);
@@ -786,18 +836,21 @@ select {
   .provider-row,
   .provider-local,
   .schedule-controls,
-  .save-bar {
+  .save-bar,
+  .reader-error-actions {
     grid-template-columns: 1fr;
   }
 
   .save-bar,
   .save-bar div,
-  .provider-actions {
+  .provider-actions,
+  .reader-error-actions {
     justify-content: stretch;
   }
 
   .save-bar div,
-  .provider-actions {
+  .provider-actions,
+  .reader-error-actions {
     display: grid;
     grid-template-columns: 1fr 1fr;
   }
diff --git a/apps/web/src/vite-env.d.ts b/apps/web/src/vite-env.d.ts
index 43d0709..6a99ea7 100644
--- a/apps/web/src/vite-env.d.ts
+++ b/apps/web/src/vite-env.d.ts
@@ -5,3 +5,8 @@ declare module "foliate-js/epub.js" {
   export default module;
   export const EPUB: unknown;
 }
+
+declare module "foliate-js/view.js" {
+  const module: unknown;
+  export default module;
+}