diff --git a/viewer.html b/viewer.html
index 6e733319e..7bb06ee35 100644
--- a/viewer.html
+++ b/viewer.html
@@ -5,6 +5,7 @@
 
         <script type="text/javascript" src="viewer.js"></script>
         <script type="text/javascript" src="pdf.js"></script>
+        <script type="text/javascript" src="utils/fonts_utils.js"></script>
         <script type="text/javascript" src="fonts.js"></script>
         <script type="text/javascript" src="glyphlist.js"></script>
   </head>
@@ -25,8 +26,7 @@
     <div id="viewer">
       <!-- Canvas dimensions must be specified in CSS pixels.  CSS pixels
            are always 96 dpi.  816x1056 is 8.5x11in at 96dpi. -->
-      <!-- We're rendering here at 1.5x scale. -->
-      <canvas id="canvas" width="1224" height="1584"></canvas>
+      <canvas id="canvas" width="816" height="1056" defaultwidth="816" defaultheight="1056"></canvas>
     </div>
   </body>
 </html>
diff --git a/viewer.js b/viewer.js
index 2bcff50a6..c7adee892 100644
--- a/viewer.js
+++ b/viewer.js
@@ -3,11 +3,12 @@
 
 "use strict";
 
-var pdfDocument, canvas, pageDisplay, pageNum, numPages, pageTimeout;
+var pdfDocument, canvas, pageScale, pageDisplay, pageNum, numPages, pageTimeout;
 function load(userInput) {
     canvas = document.getElementById("canvas");
     canvas.mozOpaque = true;
-    pageNum = parseInt(queryParams().page) || 1;
+    pageNum = ("page" in queryParams()) ? parseInt(queryParams().page) : 1;
+    pageScale = ("scale" in queryParams()) ? parseInt(queryParams().scale) : 1.5;
     var fileName = userInput;
     if (!userInput) {
       fileName = queryParams().file || "compressed.tracemonkey-pldi-09.pdf";
@@ -59,6 +60,8 @@ function displayPage(num) {
     var t0 = Date.now();
 
     var page = pdfDocument.getPage(pageNum = num);
+    canvas.width = parseInt(canvas.getAttribute("defaultwidth")) * pageScale;
+    canvas.height = parseInt(canvas.getAttribute("defaultheight")) * pageScale;
 
     var t1 = Date.now();
     var ctx = canvas.getContext("2d");