diff --git a/lib/ace/layer/gutter.js b/lib/ace/layer/gutter.js
index cd8622d8..5a535094 100644
--- a/lib/ace/layer/gutter.js
+++ b/lib/ace/layer/gutter.js
@@ -214,7 +214,7 @@ var Gutter = function(parentEl) {
         this.element.style.height = config.minHeight + "px";
 
         if (this.$fixedWidth || session.$useWrapMode)
-            lastLineNumber = session.getLength();
+            lastLineNumber = session.getLength() + firstLineNumber;
 
         var gutterWidth = gutterRenderer 
             ? gutterRenderer.getWidth(session, lastLineNumber, config)