diff --git a/html/diffHighlighter.js b/html/diffHighlighter.js
index fb5ac73..43274bd 100644
--- a/html/diffHighlighter.js
+++ b/html/diffHighlighter.js
@@ -18,7 +18,7 @@ var highlightDiffs = function() {
 			if (l.length > 250)
 			l = l.substring(0, 250);
 
-			l = l.gsub("\t", "  ");
+			l = l.gsub("\t", "    ");
 
 			if (l.startsWith("diff")) {
 				line1 += "\n";
@@ -43,6 +43,10 @@ var highlightDiffs = function() {
 			}
 
 			if (l.startsWith("+")) {
+				// Highlight trailing whitespace
+				if (m = l.match(/([\t ]+)$/))
+				   l = l.replace(/[\t ]+$/, "<span class='whitespace'>" + m[1] + "</span>");
+
 				line1 += "\n";
 				line2 += ++hunk_start_line_2 + "\n";
 				diffContent += "<div class='addline'>" + l + "</div>";
diff --git a/html/diff_style.css b/html/diff_style.css
index 9c32cf1..781e35b 100644
--- a/html/diff_style.css
+++ b/html/diff_style.css
@@ -39,6 +39,11 @@ pre code {
 	border-left: 5px solid black;
 }
 
+.whitespace {
+	background-color: rgba(255,0,0,0.5);
+}
+
+
 table.diff {
 	margin-top: 15px;
 	margin-left: 5px;