diff --git a/main.ts b/main.ts
index 2b9125f..518ca49 100644
--- a/main.ts
+++ b/main.ts
@@ -709,6 +709,7 @@ if (
 
 // Native resize tracking using Deno 2.9 BrowserWindow events
 let resizeTimer: ReturnType<typeof setTimeout> | undefined;
+let sizeSeenFromEvent = false;
 try {
   win.addEventListener(
     "resize",
@@ -720,6 +721,7 @@ try {
       if (w >= 1100 && h >= 700) {
         settings.windowWidth = w;
         settings.windowHeight = h;
+        sizeSeenFromEvent = true;
       }
       resizeTimer = setTimeout(() => {
         if (settings.windowWidth >= 1100 && settings.windowHeight >= 700) {
@@ -740,17 +742,28 @@ try {
     "close",
     (() => {
       if (resizeTimer !== undefined) clearTimeout(resizeTimer);
-      const [fw, fh] = win.getSize();
-      if (fw >= 1100 && fh >= 700) {
-        settings.windowWidth = fw;
-        settings.windowHeight = fh;
+      // Prefer the size reported by native resize events. getSize() has
+      // been observed to return a stale value (the last programmatically
+      // requested size) instead of the actual user-resized window size,
+      // which caused the same size to be saved on every close. Only fall
+      // back to getSize() if no resize event was ever received.
+      if (!sizeSeenFromEvent) {
+        try {
+          const [fw, fh] = win.getSize();
+          if (fw >= 1100 && fh >= 700) {
+            settings.windowWidth = fw;
+            settings.windowHeight = fh;
+          }
+        } catch { /* ok */ }
       }
       try {
         const path = resolveSettingsPath();
         Deno.mkdirSync(dirname(path), { recursive: true });
         Deno.writeTextFileSync(path, JSON.stringify(settings, null, 2));
         console.log(
-          `${PREFIX} Window size saved on close: ${settings.windowWidth}x${settings.windowHeight}`,
+          `${PREFIX} Window size saved on close: ${settings.windowWidth}x${settings.windowHeight} (source: ${
+            sizeSeenFromEvent ? "resize events" : "getSize()"
+          })`,
         );
       } catch (err) {
         console.error(
diff --git a/web/app.js b/web/app.js
index ff51b4d..4391290 100644
--- a/web/app.js
+++ b/web/app.js
@@ -126,10 +126,11 @@ async function loadPdf(index) {
   }
   loadedIndex = index;
 
+  const previousZoom = pdfViewer ? pdfViewer.zoom : 1;
   if (pdfViewer) {
     pdfViewer.destroy();
   }
-  pdfViewer = new PdfViewer(pdfContainer);
+  pdfViewer = new PdfViewer(pdfContainer, { initialZoom: previousZoom });
   viewer.classList.remove("loaded");
   pdfMessage.hidden = false;
   pdfMessage.textContent = "Loading PDF\u2026";
diff --git a/web/pdf_viewer.js b/web/pdf_viewer.js
index 2f369f2..9e917d7 100644
--- a/web/pdf_viewer.js
+++ b/web/pdf_viewer.js
@@ -6,7 +6,7 @@ const ZOOM_MAX = 5;
 const ZOOM_STEP = 1.2; // multiplicative
 
 class PdfViewer {
-  constructor(container) {
+  constructor(container, options = {}) {
     this.container = container;
     this.generation = 0;
     this.loadingTask = null;
@@ -15,12 +15,18 @@ class PdfViewer {
     this.renderTasks = new Set();
     this.lastUrl = null;
     this.lastSize = null;
-    this.zoom = 1; // multiplier on fit-to-width (1 = fit width)
+    // multiplier on fit-to-width (1 = fit width); can be seeded from the
+    // previous viewer instance so zoom survives switching documents
+    this.zoom = Math.min(
+      ZOOM_MAX,
+      Math.max(ZOOM_MIN, options.initialZoom ?? 1),
+    );
     this._lastRenderWidth = 0;
     this._resizeTimer = null;
     this._zoomTimer = null;
     this.resizeObserver = null;
     this._createDOM();
+    this._updateZoomLabel();
     this._observeResize();
   }