diff --git a/src/main/scala/org/scalajs/dom/ext/Extensions.scala b/src/main/scala/org/scalajs/dom/ext/Extensions.scala
index c8300f4a6..be6c8159a 100644
--- a/src/main/scala/org/scalajs/dom/ext/Extensions.scala
+++ b/src/main/scala/org/scalajs/dom/ext/Extensions.scala
@@ -154,9 +154,12 @@ object KeyCode {
 import scala.concurrent.{Promise, Future}
 /**
  * Thrown when `Ajax.get` or `Ajax.post` receives a non-20X response code.
- * Contains the XMLHttpRequest that resulted in that respons
+ * Contains the XMLHttpRequest that resulted in that response
  */
-case class AjaxException(xhr: dom.XMLHttpRequest) extends Exception
+case class AjaxException(xhr: dom.XMLHttpRequest) extends Exception {
+  def isTimeout = xhr.status == 0 && xhr.readyState == 4
+}
+
 /**
  * Wraps an XMLHttpRequest to provide an easy one-line way of making 
  * an Ajax call, returning a Future.