Index: lib/Rewrite/HTMLRewrite.cpp
===================================================================
--- lib/Rewrite/HTMLRewrite.cpp
+++ lib/Rewrite/HTMLRewrite.cpp
@@ -342,6 +342,7 @@
       " .CodeInsertionHint { font-weight: bold; background-color: #10dd10 }\n"
       " .CodeRemovalHint { background-color:#de1010 }\n"
       " .CodeRemovalHint { border-bottom:1px solid #6F9DBE }\n"
+      " .selected{ background-color:orange !important; }\n"
       " table.simpletable {\n"
       "   padding: 5px;\n"
       "   font-size:12pt;\n"
Index: lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
===================================================================
--- lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
+++ lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
@@ -91,6 +91,9 @@
   // Rewrite the file specified by FID with HTML formatting.
   void RewriteFile(Rewriter &R, const SourceManager& SMgr,
                    const PathPieces& path, FileID FID);
+
+  /// \return Javascript for navigating the HTML report using j/k keys.
+  std::string generateKeyboardNavigationJavascript();
 };
 
 } // end anonymous namespace
@@ -337,6 +340,9 @@
   int LineNumber = path.back()->getLocation().asLocation().getExpansionLineNumber();
   int ColumnNumber = path.back()->getLocation().asLocation().getExpansionColumnNumber();
 
+  R.InsertTextBefore(SMgr.getLocForStartOfFile(FID),
+                     generateKeyboardNavigationJavascript());
+
   // Add the name of the file as an <h1> tag.
   {
     std::string s;
@@ -380,6 +386,7 @@
 
     os << "</table>\n<!-- REPORTSUMMARYEXTRA -->\n"
           "<h3>Annotated Source Code</h3>\n";
+    os << "<p>Use j/k keys for keyboard navigation</p>\n";
 
     R.InsertTextBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }
@@ -777,3 +784,61 @@
 
   html::HighlightRange(R, InstantiationStart, E, HighlightStart, HighlightEnd);
 }
+
+std::string HTMLDiagnostics::generateKeyboardNavigationJavascript() {
+  return R"<<<(
+<script type='text/javascript'>
+var currentSelected = 0;
+
+var move = function(num, up, numItems) {
+  if (num == 1 && up || num == numItems - 1 && !up) {
+    return 0;
+  } else if (num == 0 && up) {
+    return numItems - 1;
+  } else if (num == 0 && !up) {
+    return 1 % numItems;
+  }
+  return up ? num - 1 : num + 1;
+}
+
+var numToId = function(num) {
+  if (num == 0) {
+    return "EndPath"
+  }
+  return "Path" + num;
+};
+
+var navigateTo = function(up) {
+  var numItems = document.getElementsByClassName("msg").length;
+  var newSelected = move(currentSelected, up, numItems);
+
+  var elId = numToId(currentSelected, numItems);
+  var newElId = numToId(newSelected, numItems);
+
+  var el = document.getElementById(elId);
+  var newEl = document.getElementById(newElId);
+
+  el.classList.remove("selected");
+  newEl.classList.add("selected");
+
+  // Scroll element into center.
+  window.scrollBy(0, newEl.getBoundingClientRect().top -
+      (window.innerHeight / 2));
+
+  currentSelected = newSelected;
+};
+
+window.addEventListener("keydown", function (event) {
+  if (event.defaultPrevented) {
+    return;
+  }
+  if (event.key == "j") {
+    navigateTo(/*up=*/false);
+  } else if (event.key == "k") {
+    navigateTo(/*up=*/true);
+  }
+  event.preventDefault();
+}, true);
+</script>
+  )<<<";
+}