diff --git a/web/viewer.js b/web/viewer.js
index b8fe3bca2..7a76085cf 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -359,7 +359,9 @@ var PDFView = {
           scale = Math.min(pageWidthScale, pageHeightScale);
           break;
         case 'auto':
-          scale = Math.min(MAX_AUTO_SCALE, pageWidthScale);
+          var isLandscape = (currentPage.width > currentPage.height);
+          var horizontalScale = isLandscape ? pageHeightScale : pageWidthScale;
+          scale = Math.min(MAX_AUTO_SCALE, horizontalScale);
           break;
         default:
           console.error('pdfViewSetScale: \'' + value +
@@ -1211,7 +1213,7 @@ var PDFView = {
   setInitialView: function pdfViewSetInitialView(storedHash, scale) {
     // Reset the current scale, as otherwise the page's scale might not get
     // updated if the zoom level stayed the same.
-    this.currentScale = 0;
+    this.currentScale = UNKNOWN_SCALE;
     this.currentScaleValue = null;
     // When opening a new file (when one is already loaded in the viewer):
     // Reset 'currentPageNumber', since otherwise the page's scale will be wrong