diff --git a/examples/icon-sprite-webgl.js b/examples/icon-sprite-webgl.js
index 7f65cb3e27..04d0fb160b 100644
--- a/examples/icon-sprite-webgl.js
+++ b/examples/icon-sprite-webgl.js
@@ -78,14 +78,8 @@ var vector = new ol.layer.Vector({
   source: vectorSource
 });
 
-// Use the "webgl" renderer by default.
-var renderer = common.getRendererFromQueryString();
-if (!renderer) {
-  renderer = 'webgl';
-}
-
 var map = new ol.Map({
-  renderer: renderer,
+  renderer: common.getRendererFromQueryString('webgl'),
   layers: [vector],
   target: document.getElementById('map'),
   view: new ol.View({
diff --git a/examples/resources/common.js b/examples/resources/common.js
index 82a902d824..799e607283 100644
--- a/examples/resources/common.js
+++ b/examples/resources/common.js
@@ -83,7 +83,7 @@
 
 var common = {};
 
-common.getRendererFromQueryString = function() {
+common.getRendererFromQueryString = function(opt_default) {
   var obj = {};
   var queryString = location.search.slice(1);
   var re = /([^&=]+)=([^&]*)/g;
@@ -98,6 +98,6 @@ common.getRendererFromQueryString = function() {
   } else if ('renderer' in obj) {
     return [obj['renderer']];
   } else {
-    return undefined;
+    return opt_default;
   }
 };
diff --git a/examples/symbol-atlas-webgl.js b/examples/symbol-atlas-webgl.js
index df227e2138..9a994013b6 100644
--- a/examples/symbol-atlas-webgl.js
+++ b/examples/symbol-atlas-webgl.js
@@ -106,14 +106,8 @@ var vector = new ol.layer.Vector({
   source: vectorSource
 });
 
-// Use the "webgl" renderer by default.
-var renderer = common.getRendererFromQueryString();
-if (!renderer) {
-  renderer = 'webgl';
-}
-
 var map = new ol.Map({
-  renderer: renderer,
+  renderer: common.getRendererFromQueryString('webgl'),
   layers: [vector],
   target: document.getElementById('map'),
   view: new ol.View({
diff --git a/externs/example.js b/externs/example.js
index 5fcec4903a..9ccb94b6ad 100644
--- a/externs/example.js
+++ b/externs/example.js
@@ -6,9 +6,10 @@ var common;
 
 
 /**
+ * @param {string=} opt_default Default renderer.
  * @return {string} Renderer type.
  */
-common.getRendererFromQueryString = function() {};
+common.getRendererFromQueryString = function(opt_default) {};
 
 
 /**